Fix warnings

This patch fixes:

  clang-tools-extra/clangd/Hover.cpp:1036:28: warning: unused variable
  ‘MTE’ [-Wunused-variable]

  llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:22295:19: error:
  unused variable 'AN' [-Werror,-Wunused-variable]

Author: kazutakahirata

clang-tools-extra/clangd/Hover.cpp

@@ -1033,8 +1033,7 @@ void maybeAddCalleeArgInfo(const SelectionTree::Node *N, HoverInfo &HI,
         PassType.PassBy = HoverInfo::PassType::Value;
       else
         PassType.Converted = true;
-    } else if (const auto *MTE =
-                   CastNode->ASTNode.get<MaterializeTemporaryExpr>()) {
+    } else if (CastNode->ASTNode.get<MaterializeTemporaryExpr>()) {
       // Can't bind a non-const-ref to a temporary, so has to be const-ref
       PassType.PassBy = HoverInfo::PassType::ConstRef;
     } else { // Unknown implicit node, assume type conversion.

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

@@ -22292,8 +22292,7 @@ void AArch64TargetLowering::ReplaceNodeResults(
   case ISD::ATOMIC_LOAD_AND:
   case ISD::ATOMIC_LOAD_OR:
   case ISD::ATOMIC_SWAP: {
-    AtomicSDNode *AN = cast<AtomicSDNode>(N);
-    assert(AN->getVal().getValueType() == MVT::i128 &&
+    assert(cast<AtomicSDNode>(N)->getVal().getValueType() == MVT::i128 &&
            "Expected 128-bit atomicrmw.");
     // These need custom type legalisation so we go directly to instruction.
     ReplaceATOMIC_LOAD_128Results(N, Results, DAG, Subtarget);