[llvm] [PowerPC] Utilize `getReservedRegs` to find asm clobberable registers. (PR #99766)

[Kai Luo via llvm-commits]

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@@ -8,18 +8,18 @@ alignment: 8
 tracksRegLiveness: true
 body: |
   bb.0.entry:
-  liveins: $x3, $x4
+  liveins: $x5, $x4
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bzEq wrote:

Why replace `r3` with `r5`?

https://github.com/llvm/llvm-project/pull/99766