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

[Kai Luo via llvm-commits]

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@@ -62,6 +63,7 @@ frameInfo:
 machineFunctionInfo: {}
 body:             |
   bb.0.entry:
+    liveins: $x3, $x2
     %0:g8rc = LBZ8 @y + 1, $x2 :: (dereferenceable load (s8) from @y + 1, basealign 4)
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bzEq wrote:

Same here, `r2` here is also used as toc pointer.

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