[mlir] Fix compile error.

Inside a templated function, other class members need to be called with
this->.
Otherwise we get: explicit qualification required to use member
'setDebugName' from dependent base class.

mlir/include/mlir/IR/PatternMatch.h

@@ -971,7 +971,7 @@ class RewritePatternSet {
       FnPattern(LogicalResult (*implFn)(OpType, PatternRewriter &rewriter),
                 MLIRContext *context)
           : OpRewritePattern<OpType>(context), implFn(implFn) {
-        setDebugName(llvm::getTypeName<FnPattern>());
+        this->setDebugName(llvm::getTypeName<FnPattern>());
       }
 
       LogicalResult matchAndRewrite(OpType op,