[llvm] [M68k] Add remaining addressing modes for Atomic operations (PR #115523)

[via llvm-commits]

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@@ -708,6 +708,20 @@ bool M68kDAGToDAGISel::SelectARIPD(SDNode *Parent, SDValue N, SDValue &Base) {
   return false;
 }
 
+static bool allowARIDWithDisp(SDNode *Parent) {
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knickish wrote:

style guide was unclear about what do in this case, so I added `[[maybe_unused]]` here

https://github.com/llvm/llvm-project/pull/115523