intel/compiler: Re-prefix non-logical surface opcodes with VEC4

intel/compiler: Re-prefix non-logical surface opcodes with VEC4

The scalar back-end uses SHADER_OPCODE_SEND for all surface messages so
we no longer need the non-logical opcodes there.  Prefix them VEC4 so
it's clear that they're only used by the vec4 back-end.

Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>