[llvm] [RegisterCoalescer] Fix SUBREG_TO_REG handling in the RegisterCoalescer. (PR #96839)

[Kai Luo via llvm-commits]

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@@ -0,0 +1,37 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
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bzEq wrote:

Pre-commit this case to show where `MachineVerifier` complains when specifying `-verify-coalescing -enable-subreg-liveness=true`?

https://github.com/llvm/llvm-project/pull/96839