rtc: RTC class driver for the ds1374

This patch adds an RTC class driver for the Maxim/Dallas 1374 RTC chip,
based on drivers/i2c/chips/ds1374.c.  It supports alarm functionality.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>