[llvm] [PowerPC] Add test after #75271 on PPC. NFC. (PR #75616)

[Kai Luo via llvm-commits]

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@@ -0,0 +1,9039 @@
+# RUN: llc -mtriple=powerpc64le-unknown-linux-gnu -verify-coalescing -run-pass=register-coalescer \
+# RUN:   -o - %s | FileCheck %s
+--- |
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bzEq wrote:

Tried `llvm-reduce`, still 5000+ lines of mir. I'll try to simplify LLVM IR...

https://github.com/llvm/llvm-project/pull/75616