modify dir of dep in OpenMPCommon

Fix dir error of deps in OpenMPCommon bazel build

Differential Revision: https://reviews.llvm.org/D146461

Author: yijia1212

utils/bazel/llvm-project-overlay/mlir/BUILD.bazel

@@ -6762,8 +6762,8 @@ cc_library(
     deps = [
         ":IR",
         ":Support",
-        "//third_party/llvm/llvm-project/llvm:Core",
-        "//third_party/llvm/llvm-project/llvm:FrontendOpenMP",
+        "//llvm:Core",
+        "//llvm:FrontendOpenMP",
     ],
 )