rtc: m48t59 fix section mismatch warning

Change the name of this data to use a name (suffix) that is whitelisted
by MODPOST so that the section warning is fixed (not generated).

WARNING: vmlinux.o(.data+0x1b140): Section mismatch: reference to .init.text:m48t59_rtc_probe (between 'm48t59_rtc_platdrv' and 'm48t59_nvram_attr')

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.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>