AMD target bit codes

Hi Jon,
Do you guys build all of the generations of AMD GPUs, by default?

[...]
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx700.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx701.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx801.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx803.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx900.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx902.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx906.bc
-- Installing: /p/project/cjzam11/kitayama1/dev/clang/lib/libomptarget-amdgcn-gfx908.bc
[...]

As always, I am on the latest `main` branch.

Yes, always. Ye