Currently the rtc driver, rtc-ds1742.c uses an unsigned long to store the
base mmio address of the NVRAM/RTC.  This breaks on systems like PowerPC
440, which is a 32-bit core with 36-bit physical addresses: IO on the
system, including the RTC, is typically above the 4GB point, and cannot fit
into an unsigned long.

This patch fixes the problem by replacing the unsigned long with a
resource_size_t.  Tested on Ebony (PPC440) (with additional patches to
instantiate the ds1742 platform device appropriately).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: 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>