[llvm] [AMDGPU] misched: avoid subregister dependencies (PR #140255)

[Shilei Tian via llvm-commits]

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@@ -272,6 +272,17 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
   SITargetLowering TLInfo;
   SIFrameLowering FrameLowering;
 
+  /// From the (MI300) ISA:
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shiltian wrote:

use `gfx` number here instead of MI name

https://github.com/llvm/llvm-project/pull/140255