I am using a Xircom CEM33 pcmcia NIC which has occasional hardware problems.
If the netdev watchdog detects a transmit timeout, do_reset is called which
msleeps - this is illegal in atomic context.

This patch schedules the timeout handling as a workqueue item.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>