[llvm] [AMDGPU][AsmParser] Allow `v_writelane_b32` to use SGPR and M0 as source operands at the same time (PR #78827)

[Joe Nash via llvm-commits]

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@@ -0,0 +1,14 @@
+// RUN: llvm-mc --triple=amdgcn --mcpu=gfx904 -show-encoding %s | FileCheck %s -check-prefix=GFX9
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Sisyph wrote:

Looks like it needs a check line for gfx6/gfx7. Otherwise LGTM

https://github.com/llvm/llvm-project/pull/78827