Enable RTC driver.

The MC13783 MFD also contains an RTC. Enable it.
To avoid "No RTC device found, ALARM timers will not wake from suspend",
this patch is needed:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=c008ba58af24dc5d0d8e9fe6e59d876910254761



Signed-off-by: Jürgen Lambrecht <J.Lambrecht@televic.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>