[llvm] [AMDGPU] fix eliminateFrameIndex to use SGPR frame index (PR #178991)

[via llvm-commits]

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@@ -0,0 +1,35 @@
+; RUN: llc -mtriple=amdgcn -mcpu=gfx1030  < %s | FileCheck %s
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bcahoon wrote:

Does this test fail without this PR? If so, on what instruction and operand?

https://github.com/llvm/llvm-project/pull/178991