[llvm] [AMDGPU] Add legalizer rule support for AMDGPU's regbank fminimumnum and fmaximumnum (PR #192719)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,364 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
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arsenm wrote:

Is a mir test really necessary? 

https://github.com/llvm/llvm-project/pull/192719