nir: Rename nir_intrinsic_barrier to control_barrier

This is a more explicit name now that we don't want it to be doing any
memory barrier stuff for us.

Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3307>

src/intel/compiler/brw_vec4_tcs.cpp

@@ -308,7 +308,7 @@ vec4_tcs_visitor::nir_emit_intrinsic(nir_intrinsic_instr *instr)
       break;
    }
 
-   case nir_intrinsic_barrier: {
+   case nir_intrinsic_control_barrier: {
       dst_reg header = dst_reg(this, glsl_type::uvec4_type);
       emit(TCS_OPCODE_CREATE_BARRIER_HEADER, header);
       emit(SHADER_OPCODE_BARRIER, dst_null_ud(), src_reg(header));