[llvm] [AMDGPU][SIInsertWaitcnts][NFC] Drop MaxCounter member variable (PR #181092)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -1984,7 +1990,7 @@ WaitcntGeneratorGFX12Plus::getAllZeroWaitcnt(bool IncludeVSCnt) const {
 bool WaitcntGeneratorGFX12Plus::applyPreexistingWaitcnt(
     WaitcntBrackets &ScoreBrackets, MachineInstr &OldWaitcntInstr,
     AMDGPU::Waitcnt &Wait, MachineBasicBlock::instr_iterator It) const {
-  assert(!isNormalMode(MaxCounter));
+  assert(!isNormalMode(getMaxCounter(ST, IsExpertMode)));
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ssahasra wrote:

`isNormalMode` is never used outside of WaitcntGenerator. It should be made a private const member of that class instead of polluting the file's namespace.

https://github.com/llvm/llvm-project/pull/181092