Add support for the MAX6902 SPI RTC chip.  Tested on a pxa2xx cpu.

The compulab code comes from the kernel patch the produce for their
cn-x255 board. (inside a zip file on the
http://www.compulab.co.il/x255/html/x255-developer.htm)

The original file (drivers/char/max6902.c) was GPL, which is of course
an appropriate licence:

/*
 * max6902.c
 *
 * Driver for MAX6902 RTC
 *
 * Copyright (C) 2004 Compulab Ltd.
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *
 */

For reference, you can get the original file here:
http://raph.people.8d.com/misc/max6902.c

[akpm@osdl.org: cleanups]
Signed-off-by: Raphael Assenat <raph@raphnet.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>