rtc-at91sam9 fixes

Updates to the at91sam9 rtt-as-rtc driver:

 - Bugfix:  IRQ enable bits need shifting before masking with status
 - Platform code to initialize wakeup bits didn't get merged; cope

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Justin Waters <justin.waters@timesys.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>