Integrate LLVM at llvm/llvm-project@c266c56d54

Updates LLVM usage to match
[c266c56d545d](https://github.com/llvm/llvm-project/commit/c266c56d545d)

PiperOrigin-RevId: 345222350
Change-Id: I5916e5408287ead2ead35c031b7e75a16d9b0a73

tensorflow/workspace.bzl

@@ -686,8 +686,8 @@ def tf_repositories(path_prefix = "", tf_repo_name = ""):
     )
 
     # Check out LLVM and MLIR from llvm-project.
-    LLVM_COMMIT = "aafb3662103f4b3df315967c0cf4f6eec6bff0c4"
-    LLVM_SHA256 = "6f3a0b9e7aae732fa25754f993057fe8833caf14da556071af320ad3e7785f4c"
+    LLVM_COMMIT = "c266c56d545dfecf767b312771f716b394c5d5eb"
+    LLVM_SHA256 = "5a3a780bb5679f8e47c770cd049d9f0c8248cb1c3310db59245ab7475e221625"
     LLVM_URLS = [
         "https://storage.googleapis.com/mirror.tensorflow.org/github.com/llvm/llvm-project/archive/{commit}.tar.gz".format(commit = LLVM_COMMIT),
         "https://github.com/llvm/llvm-project/archive/{commit}.tar.gz".format(commit = LLVM_COMMIT),

third_party/mlir/BUILD

@@ -2513,9 +2513,13 @@ cc_library(
     hdrs = glob(["include/mlir/Rewrite/*.h"]),
     includes = ["include"],
     deps = [
+        ":Analysis",
         ":IR",
+        ":PDLDialect",
+        ":PDLInterpDialect",
+        ":PDLToPDLInterp",
         ":Pass",
-        ":Support",
+        ":SideEffectInterfaces",
         "@llvm-project//llvm:Support",
     ],
 )
@@ -3278,6 +3282,7 @@ cc_library(
         "@llvm-project//mlir/test:TestIR",
         "@llvm-project//mlir/test:TestPass",
         "@llvm-project//mlir/test:TestReducer",
+        "@llvm-project//mlir/test:TestRewrite",
         "@llvm-project//mlir/test:TestSPIRV",
         "@llvm-project//mlir/test:TestShapeDialect",
         "@llvm-project//mlir/test:TestTransforms",

third_party/mlir/test.BUILD

@@ -205,6 +205,19 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "TestRewrite",
+    srcs = [
+        "lib/Rewrite/TestPDLByteCode.cpp",
+    ],
+    deps = [
+        "@llvm-project//mlir:IR",
+        "@llvm-project//mlir:Pass",
+        "@llvm-project//mlir:Support",
+        "@llvm-project//mlir:TransformUtils",
+    ],
+)
+
 cc_library(
     name = "TestReducer",
     srcs = [