qed: Mark expected switch fall-through

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

This patch fixes the following warning:

drivers/net/ethernet/qlogic/qed/qed_cxt.c:2126:4: warning: this statement may fall through [-Wimplicit-fallthrough=]

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/qlogic/qed/qed_cxt.c

@@ -2129,6 +2129,7 @@ int qed_cxt_set_pf_params(struct qed_hwfn *p_hwfn, u32 rdma_tasks)
 					       rdma_tasks);
 		/* no need for break since RoCE coexist with Ethernet */
 	}
+	/* fall through */
 	case QED_PCI_ETH:
 	{
 		struct qed_eth_pf_params *p_params =