Commit 17176c2 adds a test of a new RTC
register flag to distinguish a system reset and a wake up event. Shame on me,
I have forgotten to define the newly used flag yet.
While already here, I also try to document the other flags the RTC provides.
Signed-off-by: Juergen Beisert <jbe@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>