From: Like Xu<likexu@xxxxxxxxxxx>
The find_arch_event() returns a "unsigned int" value,
which is used by the pmc_reprogram_counter() to
program a PERF_TYPE_HARDWARE type perf_event.
The returned value is actually the kernel defined gernic
perf_hw_id, let's rename it to find_perf_hw_id() with simpler
incoming parameters for better self-explanation.