[llvm] [AMDGPU][True16][CodeGen] true16 codegen pattern for fma (PR #122950)

[Brox Chen via llvm-commits]

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@@ -1,17 +1,10 @@
 # NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
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broxigarchen wrote:

updated this file to be true16 and added a fake16 file

https://github.com/llvm/llvm-project/pull/122950