net: core: Fix fall-through warnings for Clang

In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning by explicitly adding a break statement instead of letting the code fall through to the next case.

---
Changes in RESEND:
- None. Resending now that net-next is open.

 net/core/dev.c | 1 +
 1 file changed, 1 insertion(+)

index 6c5967e80132..2bfdd528c7c3 100644
@@ -5265,6 +5265,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 			goto another_round;
 		case RX_HANDLER_EXACT:
 			deliver_exact = true;
+			break;
 		case RX_HANDLER_PASS:
 			break;
 		default:

2.27.0