[AMDGPU][OpenMP] Add amdgpu-arch tool to list AMD GPUs installed

This patch adds new clang tool named amdgpu-arch which uses
HSA to detect installed AMDGPU and report back latter's march.
This tool is built only if system has HSA installed.

The value printed by amdgpu-arch is used to fill -march when
latter is not explicitly provided in -Xopenmp-target.

Reviewed By: JonChesterfield, gregrodgers

Differential Revision: https://reviews.llvm.org/D99949

GitOrigin-RevId: 7029cffc4e78556cfe820791c612968bb15b2ffb
14 files changed