add clew.h to cocl_unittests includes
add clew.h to cocl_unittests includes

hughperkins/cuda-on-cl,hughperkins/coriander,hughperkins/coriander,hughperkins/cuda-on-cl,hughperkins/coriander,hughperkins/cuda-on-cl,hughperkins/cuda-on-cl,hughperkins/coriander