message: Add OpenMP dialect to the dialect registry
  Closes
  COPYBARA_INTEGRATE_REVIEW=https://github.com/tensorflow/mlir/pull/244 from DavidTruby:openmp
diff: @@ -29,6 +29,7 @@ DEFINE_SYM_KIND_RANGE(QUANTIZATION)
  DEFINE_SYM_KIND_RANGE(IREE) // IREE stands for IR Execution Engine
  DEFINE_SYM_KIND_RANGE(LINALG) // Linear Algebra Dialect
  DEFINE_SYM_KIND_RANGE(FIR) // Flang Fortran IR Dialect
  +DEFINE_SYM_KIND_RANGE(OPENMP) // OpenMP IR Dialect
  DEFINE_SYM_KIND_RANGE(TOY) // Toy language (tutorial) Dialect
  DEFINE_SYM_KIND_RANGE(SPIRV) // SPIR-V dialect
  