m68k: add ColdFire with MMU enabled support to the m68k mem init code

The ColdFire has similar setup requirements to the SUN3 code, so we
use that.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Matt Waddel <mwaddel@yahoo.com>
Acked-by: Kurt Mahan <kmahan@xmission.com>