rtc: add pcf85063 support

Add support for the pcf85063 rtc chip.

[akpm@linux-foundation.org: fix comment typo, tweak conding style]
Signed-off-by: Soeren Andersen <san@rosetechnology.dk>
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>