[llvm] [AMDGPU][SDAG] Use the f16 lowering for bf16 safe divisions. (PR #147530)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm commented:

Can you add a fixme to the globalisel path so the same change is made when bfloat is supported 

https://github.com/llvm/llvm-project/pull/147530