usb: storage: uas: mark expected switch fall-through

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 115016
Signed-off-by: NGustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/storage/uas.c

@@ -668,6 +668,7 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
 		break;
 	case DMA_BIDIRECTIONAL:
 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
+		/* fall through */
 	case DMA_TO_DEVICE:
 		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
 	case DMA_NONE: