[llvm] [AMDGPU] Fully remove the old renamedInGFX9 flag from TSFlags. NFC. (PR #219191)

[Jay Foad via llvm-commits]

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@@ -218,9 +218,6 @@ class InstSI <dag outs, dag ins, string asm = "",
 
   let TSFlags{43} = maybeAtomic;
 
-  // Reserved, must be 0.
-  let TSFlags{44} = 0;
-
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jayfoad wrote:

We don't bother with this for other unused bits, 11 and 31.

https://github.com/llvm/llvm-project/pull/219191