[llvm] [SelectionDAG] Fix soft-promotion of f16 BUILD_VECTOR for MSA targets (PR #210515)

[Matt Arsenault via llvm-commits]

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@@ -1,41 +1,146 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
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arsenm wrote:

Generally should pre-commit the conversion to generated checks 

https://github.com/llvm/llvm-project/pull/210515