Fix warning caused by TableGen verifier predicate (NFC)

Avoid using max on unsigned constants, in case the caller is using 0 we
end up with:

  warning: taking the max of unsigned zero and a value is always equal to the other value [-Wmax-unsigned-zero]

Instead we can just use native TableGen to fold the comparison here.

mlir/include/mlir/IR/OpBase.td

@@ -2073,7 +2073,7 @@ class ElementTypeIs<string name, Type type> : PredOpTrait<
 // Type Constraint operand `i`'s Element type is Same As operand `j`'s Element
 // type.
 class TCopVTEtIsSameAs<int i, int j> : And<[
-    CPred<"$_op.getNumOperands() > std::max(" # i # "u," # j # "u)">,
+    CPred<"$_op.getNumOperands() > " # !if(!gt(i,j),i,j)>,
     SubstLeaves<"$_self", "$_op.getOperand(" # i # ").getType()",
       IsShapedTypePred>,
     SubstLeaves<"$_self", "$_op.getOperand(" # j # ").getType()",