Disable x86 (32-bit) Linux builds or issue a warning

Tried to make a 32-bit ChakraCore build for Linux (Ubuntu), but the build failed. I was able to build for x64 without a hitch, but x86 proved futile.

Command line:

fatcerberus@pigcult-vm:~/src/ChakraCore$ ./build.sh --embed-icu -j=4 --lto --arch=x86

Gave me the following output:

lto: ranlib disabled
Custom CXX /home/fatcerberus/src/ChakraCore/cc-toolchain/build/bin/clang++
Custom CC  /home/fatcerberus/src/ChakraCore/cc-toolchain/build/bin/clang
Build path: /home/fatcerberus/src/ChakraCore/out/Release
-- /home/fatcerberus/src/ChakraCore/bin/ch/DbgController.js.h is up to date. skipping.
Compile Target : x86
Generating Release makefiles

-- found ICU libs: deps/icu/source/output/include//../lib/
-- Configuring done
-- Generating done
-- Build files have been written to: /home/fatcerberus/src/ChakraCore/out/Release
[  0%] Building CXX object lib/Jsrt/Core/CMakeFiles/Chakra.Jsrt.Core.dir/JsrtContextCore.cpp.o
[  1%] Building CXX object pal/src/CMakeFiles/Chakra.Pal.dir/cruntime/file.cpp.o
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
lib/Jsrt/Core/CMakeFiles/Chakra.Jsrt.Core.dir/build.make:62: recipe for target 'lib/Jsrt/Core/CMakeFiles/Chakra.Jsrt.Core.dir/JsrtContextCore.cpp.o' failed
make[2]: *** [lib/Jsrt/Core/CMakeFiles/Chakra.Jsrt.Core.dir/JsrtContextCore.cpp.o] Error 1
CMakeFiles/Makefile2:1448: recipe for target 'lib/Jsrt/Core/CMakeFiles/Chakra.Jsrt.Core.dir/all' failed
make[1]: *** [lib/Jsrt/Core/CMakeFiles/Chakra.Jsrt.Core.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
pal/src/CMakeFiles/Chakra.Pal.dir/build.make:62: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.dir/cruntime/file.cpp.o' failed
make[2]: *** [pal/src/CMakeFiles/Chakra.Pal.dir/cruntime/file.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
[  1%] Building CXX object pal/src/CMakeFiles/Chakra.Pal.dir/cruntime/filecrt.cpp.o
[  1%] Building CXX object pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/filecrt.cpp.o
[  1%] Building CXX object pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/file.cpp.o
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
pal/src/CMakeFiles/Chakra.Pal.dir/build.make:86: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.dir/cruntime/filecrt.cpp.o' failed
make[2]: *** [pal/src/CMakeFiles/Chakra.Pal.dir/cruntime/filecrt.cpp.o] Error 1
CMakeFiles/Makefile2:142: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.dir/all' failed
make[1]: *** [pal/src/CMakeFiles/Chakra.Pal.dir/all] Error 2
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
pal/src/CMakeFiles/Chakra.Pal.Singular.dir/build.make:62: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/file.cpp.o' failed
make[2]: *** [pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/file.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
pal/src/CMakeFiles/Chakra.Pal.Singular.dir/build.make:86: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/filecrt.cpp.o' failed
make[2]: *** [pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/filecrt.cpp.o] Error 1
[  1%] Building CXX object pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/finite.cpp.o
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
pal/src/CMakeFiles/Chakra.Pal.Singular.dir/build.make:110: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/finite.cpp.o' failed
make[2]: *** [pal/src/CMakeFiles/Chakra.Pal.Singular.dir/cruntime/finite.cpp.o] Error 1
CMakeFiles/Makefile2:105: recipe for target 'pal/src/CMakeFiles/Chakra.Pal.Singular.dir/all' failed
make[1]: *** [pal/src/CMakeFiles/Chakra.Pal.Singular.dir/all] Error 2
[  1%] Building CXX object lib/Backend/CMakeFiles/Chakra.Backend.dir/AgenPeeps.cpp.o
[  1%] Building CXX object lib/Backend/CMakeFiles/Chakra.Backend.dir/AsmJsJITInfo.cpp.o
[  1%] Building CXX object lib/Backend/CMakeFiles/Chakra.Backend.dir/Backend.cpp.o
clang-4.0clang-4.0: : errorerror: : argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]

lib/Backend/CMakeFiles/Chakra.Backend.dir/build.make:62: recipe for target 'lib/Backend/CMakeFiles/Chakra.Backend.dir/AgenPeeps.cpp.o' failed
make[2]: *** [lib/Backend/CMakeFiles/Chakra.Backend.dir/AgenPeeps.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
lib/Backend/CMakeFiles/Chakra.Backend.dir/build.make:86: recipe for target 'lib/Backend/CMakeFiles/Chakra.Backend.dir/AsmJsJITInfo.cpp.o' failed
make[2]: *** [lib/Backend/CMakeFiles/Chakra.Backend.dir/AsmJsJITInfo.cpp.o] Error 1
[  1%] Building CXX object lib/Backend/CMakeFiles/Chakra.Backend.dir/BackendApi.cpp.o
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
clang-4.0: error: argument unused during compilation: '-arch i386' [-Werror,-Wunused-command-line-argument]
lib/Backend/CMakeFiles/Chakra.Backend.dir/build.make:110: recipe for target 'lib/Backend/CMakeFiles/Chakra.Backend.dir/Backend.cpp.o' failed
make[2]: *** [lib/Backend/CMakeFiles/Chakra.Backend.dir/Backend.cpp.o] Error 1
lib/Backend/CMakeFiles/Chakra.Backend.dir/build.make:134: recipe for target 'lib/Backend/CMakeFiles/Chakra.Backend.dir/BackendApi.cpp.o' failed
make[2]: *** [lib/Backend/CMakeFiles/Chakra.Backend.dir/BackendApi.cpp.o] Error 1
CMakeFiles/Makefile2:285: recipe for target 'lib/Backend/CMakeFiles/Chakra.Backend.dir/all' failed
make[1]: *** [lib/Backend/CMakeFiles/Chakra.Backend.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2
See error details above. Exit code was 2