intel: Drop program size pointer from vec4/fs assembly getters.

These days, we're just passing a pointer to a prog_data field, which
we already have access to.  We can just use it directly.

(In the past, it was a pointer to a separate value.)

Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>

src/intel/compiler/brw_vec4.h

@@ -45,8 +45,7 @@ brw_vec4_generate_assembly(const struct brw_compiler *compiler,
                            void *mem_ctx,
                            const nir_shader *nir,
                            struct brw_vue_prog_data *prog_data,
-                           const struct cfg_t *cfg,
-                           unsigned *out_assembly_size);
+                           const struct cfg_t *cfg);
 
 #ifdef __cplusplus
 } /* extern "C" */