[llvm] [ARM] Fix failure to register-allocate CMP_SWAP_64 pseudo-inst (PR #104039)

[Matt Arsenault via llvm-commits]

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@@ -332,10 +334,11 @@ class RegAllocFastImpl {
 private:
   void allocateBasicBlock(MachineBasicBlock &MBB);
 
-  void addRegClassDefCounts(MutableArrayRef<unsigned> RegClassDefCounts,
-                            Register Reg) const;
+  void addRegClassCounts(MutableArrayRef<unsigned> RegClassDefCounts,
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arsenm wrote:

Parameter name RegClassDefCounts is now out of sync 

https://github.com/llvm/llvm-project/pull/104039