[PATCH] bcm43xx: suspend MAC while executing long pwork

Suspend MAC (and make MAC-suspend refcounting) when doing
long periodic work.
On long periodic work, we disable IRQs on the device, so
we don't want the MAC to stay operating and probably miss
packets due do non-delivery of interrupts.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>