nfp: add missing fall through statements

GCC 7 checks for fall through comments, add the two missing ones.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index c9a1403..2bcf3e8 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1687,8 +1687,10 @@
 				continue;
 			default:
 				bpf_warn_invalid_xdp_action(act);
+				/* fall through */
 			case XDP_ABORTED:
 				trace_xdp_exception(dp->netdev, xdp_prog, act);
+				/* fall through */
 			case XDP_DROP:
 				nfp_net_rx_give_one(dp, rx_ring, rxbuf->frag,
 						    rxbuf->dma_addr);