smsc911x: Call dev_consume_skb_any instead of dev_kfree_skb.

Replace dev_kfree_skb with dev_consume_skb_any in smsc911x_hard_xmit
which can be called in hard irq and other contexts. smsc911x_hard_xmit
always transmits and consumes the specified skb.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>