intel/tools: Fix compilation with UBSan

intel/tools: Fix compilation with UBSan

Compilation failed with several similar errors:

../src/intel/tools/aub_read.c:322:4: error: case label does not reduce to an integer constant
  322 |    case MAKE_HEADER(TYPE_AUB, OPCODE_AUB, SUBOPCODE_HEADER):

Signed-off-by: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4132>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4132>