USB: ohci-at91 refcount fix for irq wake enables

The attached patch fixes the unbalanced calls to enable_irq_wake() and
disable_irq_wake() in the AT91 USB Host driver.

It should resolve these kernel messages:
  Unbalanced IRQ x wake disable
  BUG: warning at kernel/irq/manage.c:167/set_irq_wake()

(The original code was debugged before a bug in the genirq wakeup irq
logic was fixed by adding the IRQ wake enable/disable refcounting.
Not all code yet uses the bugfixed model.)

Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>