The sequence counter can be accessed in IRQ context,
which means the lock protecting the counter should
be irqsave. To prevent making the entire intf->lock irqsave
without reason, create a new lock which only protects
the sequence counter.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>