[FR] Allow modification of perf attributes

Is your feature request related to a problem? Please describe.

I have a multi-threaded benchmark where I'd like the performance counters to only measure the main thread.

Describe the solution you'd like

Setting the inherit attribute to false instead of true before passing the struct to perf_event_open would solve my issue. Some sort of configuration option which allows me to set this would be ideal. Maybe this can be extended to other attributes as well instead of hardcoding them.

Describe alternatives you've considered

Currently, I have to set it to false and recompile google benchmark.