nir,compiler: expose image load/store related enums to OpenCL
for NIR->CL bindings. Example usage in libagx (this is CL code):
nir_bindless_image_store(HANDLE(uncompressed), c_sa, 0, texels[i], 0,
GLSL_SAMPLER_DIM_2D, true, 0,
ACCESS_NON_READABLE, nir_type_uint32);