This copies the change made in google benchmark (https://github.com/google/benchmark/commit/70916cbf71f50b9e1e6f13559e10d6dbb92beb32) to remove COMPILER_IBMXL for z/OS.
This copies the change made in google benchmark (https://github.com/google/benchmark/commit/70916cbf71f50b9e1e6f13559e10d6dbb92beb32) to remove COMPILER_IBMXL for z/OS.