[mlir][linalg] Clean up op verifiers without custom checks(NFC) (#168712)

This PR removes op verifiers that do not implement any custom
verification logic.

Author: CoTinker

mlir/include/mlir/Dialect/Linalg/IR/LinalgStructuredOps.td

@@ -222,7 +222,6 @@ def GenericOp : LinalgStructuredBase_Op<"generic", [
   let hasCanonicalizer = 1;
   let hasCustomAssemblyFormat = 1;
   let hasFolder = 1;
-  let hasVerifier = 1;
 }
 
 
@@ -620,7 +619,6 @@ def ElementwiseOp : LinalgStructuredBase_Op<"elementwise", [
 
   let hasCustomAssemblyFormat = 1;
   let hasFolder = 1;
-  let hasVerifier = 1;
 
   let extraClassDeclaration = structuredOpsBaseDecls # [{
       /// Get the arity enum corresponding to the kind of op, e.g. if arg is

mlir/lib/Dialect/Linalg/IR/LinalgOps.cpp

@@ -1338,8 +1338,6 @@ Speculation::Speculatability GenericOp::getSpeculatability() {
   return getGenericSpeculatabilityImpl(cast<LinalgOp>(getOperation()));
 }
 
-LogicalResult GenericOp::verify() { return success(); }
-
 namespace {
 
 /// Remove linalg operations that are just copying the values from inputs to
@@ -4885,13 +4883,6 @@ void ElementwiseOp::print(OpAsmPrinter &p) {
                          elidedAttrs);
 }
 
-LogicalResult ElementwiseOp::verify() {
-  // All necessary checks are done either by
-  // - EnumAttr (e.g. unknown operation kind)
-  // - verifyStructuredOpInterface (incorrect map, sizes).
-  return success();
-}
-
 /// Implements the block region builder for the ElementwiseOp. This is called by
 /// 'fillStructuredOpRegion'.
 void ElementwiseOp::regionBuilder(