Iterator related warnings in visual studio build

Start with src/wasm-type.h at the iterator definitions named in the Visual Studio warnings, then reproduce the build to identify the remaining iterator-related warnings. Review the affected iterator declarations and verify that the Visual Studio build no longer reports these C++17 deprecation warnings.

2>C:\src\binaryen\src\wasm-type.h(221,26): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\14.28.29333\include\xutility(6006,54): message : see declaration of 'std::iterator' (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\src\binaryen\src\wasm-type.h(251,26): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>::difference_type': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\src\binaryen\src\wasm-type.h(255,24): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>::difference_type': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\src\binaryen\src\wasm-type.h(258,26): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>::difference_type': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\src\binaryen\src\wasm-type.h(262,24): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>::difference_type': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\src\binaryen\src\wasm-type.h(265,5): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>::difference_type': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)
2>C:\src\binaryen\src\wasm-type.h(269,5): warning C4996: 'std::iterator<std::random_access_iterator_tag,wasm::Type,long,wasm::Type *,const wasm::Type &>::value_type': warning STL4015: The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. (The <iterator> header is NOT deprecated.) The C++ Standard has never required user-defined iterators to derive from std::iterator. To fix this warning, stop deriving from std::iterator and start providing publicly accessible typedefs named iterator_category, value_type, difference_type, pointer, and reference. Note that value_type is required to be non-const, even for constant iterators. You can define _SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. (compiling source file C:\src\binaryen\src\asmjs\asm_v_wasm.cpp)

And many more. Last modified here https://github.com/WebAssembly/binaryen/commit/9752196fd1357fbc129d1e4f53e8eb22cd6219f9 but it doesn't seem like the problem was introduced there.