nir: Add a new memory_barrier_tcs_patch intrinsic

Right now, it's implemented as a no-op for everyone.  For most drivers,
it's a switch case in the NIR -> whatever which just breaks.  For ir3,
they already have code to delete tessellation barriers so we just add a
case to also delete memory_barrier_tcs_patch.

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

src/intel/compiler/brw_vec4_tcs.cpp

@@ -315,6 +315,9 @@ vec4_tcs_visitor::nir_emit_intrinsic(nir_intrinsic_instr *instr)
       break;
    }
 
+   case nir_intrinsic_memory_barrier_tcs_patch:
+      break;
+
    default:
       vec4_visitor::nir_emit_intrinsic(instr);
    }