brw: Drop uniform pull constant load virtual opcode from is_send()

The logical send lowering already resolves sources when constructing
the send payload, so prior to that lowering, we don't need to apply
any special restrictions here.

Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34040>

src/intel/compiler/brw_inst.cpp

@@ -175,8 +175,6 @@ brw_inst::is_send() const
    case SHADER_OPCODE_SEND_GATHER:
    case SHADER_OPCODE_BARRIER:
       return true;
-   case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
-      return src[1].file == VGRF;
    default:
       return false;
    }