[mlir][NFC] Update textual references of `func` to `func.func` in Transform tests

The special case parsing of `func` operations is being removed.
diff --git a/mlir/test/Transforms/test-canonicalize.mlir b/mlir/test/Transforms/test-canonicalize.mlir
index 33a1db5..b845293 100644
--- a/mlir/test/Transforms/test-canonicalize.mlir
+++ b/mlir/test/Transforms/test-canonicalize.mlir
@@ -1,7 +1,7 @@
 // RUN: mlir-opt %s -pass-pipeline='func.func(canonicalize)' | FileCheck %s
 
 // CHECK-LABEL: func @remove_op_with_inner_ops_pattern
-func @remove_op_with_inner_ops_pattern() {
+func.func @remove_op_with_inner_ops_pattern() {
   // CHECK-NEXT: return
   "test.op_with_region_pattern"() ({
     "test.op_with_region_terminator"() : () -> ()
@@ -10,7 +10,7 @@
 }
 
 // CHECK-LABEL: func @remove_op_with_inner_ops_fold_no_side_effect
-func @remove_op_with_inner_ops_fold_no_side_effect() {
+func.func @remove_op_with_inner_ops_fold_no_side_effect() {
   // CHECK-NEXT: return
   "test.op_with_region_fold_no_side_effect"() ({
     "test.op_with_region_terminator"() : () -> ()
@@ -20,7 +20,7 @@
 
 // CHECK-LABEL: func @remove_op_with_inner_ops_fold
 // CHECK-SAME: (%[[ARG_0:[a-z0-9]*]]: i32)
-func @remove_op_with_inner_ops_fold(%arg0 : i32) -> (i32) {
+func.func @remove_op_with_inner_ops_fold(%arg0 : i32) -> (i32) {
   // CHECK-NEXT: return %[[ARG_0]]
   %0 = "test.op_with_region_fold"(%arg0) ({
     "test.op_with_region_terminator"() : () -> ()
@@ -30,7 +30,7 @@
 
 // CHECK-LABEL: func @remove_op_with_variadic_results_and_folder
 // CHECK-SAME: (%[[ARG_0:[a-z0-9]*]]: i32, %[[ARG_1:[a-z0-9]*]]: i32)
-func @remove_op_with_variadic_results_and_folder(%arg0 : i32, %arg1 : i32) -> (i32, i32) {
+func.func @remove_op_with_variadic_results_and_folder(%arg0 : i32, %arg1 : i32) -> (i32, i32) {
   // CHECK-NEXT: return %[[ARG_0]], %[[ARG_1]]
   %0, %1 = "test.op_with_variadic_results_and_folder"(%arg0, %arg1) : (i32, i32) -> (i32, i32)
   return %0, %1 : i32, i32
@@ -38,7 +38,7 @@
 
 // CHECK-LABEL: func @test_commutative_multi
 // CHECK-SAME: (%[[ARG_0:[a-z0-9]*]]: i32, %[[ARG_1:[a-z0-9]*]]: i32)
-func @test_commutative_multi(%arg0: i32, %arg1: i32) -> (i32, i32) {
+func.func @test_commutative_multi(%arg0: i32, %arg1: i32) -> (i32, i32) {
   // CHECK-DAG: %[[C42:.*]] = arith.constant 42 : i32
   %c42_i32 = arith.constant 42 : i32
   // CHECK-DAG: %[[C43:.*]] = arith.constant 43 : i32
@@ -54,7 +54,7 @@
 
 
 // CHECK-LABEL: func @test_commutative_multi_cst
-func @test_commutative_multi_cst(%arg0: i32, %arg1: i32) -> (i32, i32) {
+func.func @test_commutative_multi_cst(%arg0: i32, %arg1: i32) -> (i32, i32) {
   // CHECK-NEXT: %c42_i32 = arith.constant 42 : i32
   %c42_i32 = arith.constant 42 : i32
   %c42_i32_2 = arith.constant 42 : i32
@@ -71,7 +71,7 @@
 
 // CHECK-LABEL: func @typemismatch
 
-func @typemismatch() -> i32 {
+func.func @typemismatch() -> i32 {
   %c42 = arith.constant 42.0 : f32
 
   // The "passthrough_fold" folder will naively return its operand, but we don't
@@ -83,7 +83,7 @@
 }
 
 // CHECK-LABEL: test_dialect_canonicalizer
-func @test_dialect_canonicalizer() -> (i32) {
+func.func @test_dialect_canonicalizer() -> (i32) {
   %0 = "test.dialect_canonicalizable"() : () -> (i32)
   // CHECK: %[[CST:.*]] = arith.constant 42 : i32
   // CHECK: return %[[CST]]