drivers/char: comment fix: CMOS RTC update code is now in kernel/time/ntp.c

This commit updates some comments to reflect the fact that code
for periodically updating the CMOS RTC was moved to:

  kernel/time/ntp.c

probably by this commit:

  commit 82644459c592a28a3eab682f9b88d81019ddfe8b
  Author: Thomas Gleixner <tglx@linutronix.de>
  Date:   Sat Jul 21 04:37:37 2007 -0700

      NTP: move the cmos update code into ntp.c

      i386 and sparc64 have the identical code to update the cmos clock.  Move it
      into kernel/time/ntp.c as there are other architectures coming along with the
      same requirements.

Signed-off-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>