davinci_emac: Add Carrier Link OK check in Davinci RX Handler

This patch adds an additional check in the Davinci EMAC RX Handler,
which tests the __LINK_STATE_NOCARRIER flag along with the
__LINK_STATE_START flag as part EMAC shutting down procedure.

This avoids
WARNING: at drivers/net/davinci_emac.c:1040 emac_rx_handler+0xf8/0x120()
during rtcwake used to suspend the target for a specified duration.
Signed-off-by: Hegde, Vinay <vinay.hegde@ti.com>
Acked-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/davinci_emac.c

@@ -1008,7 +1008,7 @@ static void emac_rx_handler(void *token, int len, int status)
 	int			ret;
 
 	/* free and bail if we are shutting down */
-	if (unlikely(!netif_running(ndev))) {
+	if (unlikely(!netif_running(ndev) || !netif_carrier_ok(ndev))) {
 		dev_kfree_skb_any(skb);
 		return;
 	}