[llvm] [AMDGPU] Don't fix the scavenge slot at offset 0 (PR #79136)

[Diana Picus via llvm-commits]

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@@ -166,47 +166,6 @@ done:
   ret void
 }
 
-; This ends up not fitting due to the reserved 4 bytes at offset 0
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rovka wrote:

Since we don't have the reserved bytes anymore, I think we can skip this test (there's no special behavior compared to the other tests).

https://github.com/llvm/llvm-project/pull/79136