[PATCH] smc911x: Re-release spinlock on spurious interrupt

The smc911x driver forgets to release the spinlock on spurious interrupts.
This little patch fixes it.

Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>