usb: gadget: goku_udc: mark expected switch fall-throughs

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

Addresses-Coverity-ID: 145713
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/udc/goku_udc.c

@@ -127,11 +127,15 @@ goku_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
 	mode = 0;
 	max = get_unaligned_le16(&desc->wMaxPacketSize);
 	switch (max) {
-	case 64:	mode++;
-	case 32:	mode++;
-	case 16:	mode++;
-	case 8:		mode <<= 3;
-			break;
+	case 64:
+		mode++; /* fall through */
+	case 32:
+		mode++; /* fall through */
+	case 16:
+		mode++; /* fall through */
+	case 8:
+		mode <<= 3;
+		break;
 	default:
 		return -EINVAL;
 	}