[PATCH] USBATM: use dev_kfree_skb_any rather than dev_kfree_skb

In one spot (usbatm_cancel_send) we were calling dev_kfree_skb with irqs
disabled.  This mistake is just too easy to make, so systematically use
dev_kfree_skb_any rather than dev_kfree_skb.

Signed-off-by: Duncan Sands <baldrick@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>