Debug x86_32 builds fail after JDK-8239090

/home/buildbot/worker/build-jdkX-linux/build/src/hotspot/cpu/x86/vm_version_x86.cpp: In static member function 'static void VM_Version::get_processor_features()':
/home/buildbot/worker/build-jdkX-linux/build/src/hotspot/cpu/x86/vm_version_x86.cpp:782:36: error: overflow in implicit constant conversion [-Werror=overflow]
   assert(exact_log2(CPU_MAX_FEATURE) + 1 == sizeof(_features_names) / sizeof(char*), "wrong size features_names");