powerpc/mpc8xxx defconfigs - turn off SYSFS_DEPRECATED

a recent fc11 udev update on an 83xx board made root console login
disappear:

  Updating       : udev-141-8.fc11.ppc                                    32/83
udev: starting version 141
udev: deprecated sysfs layout; update the kernel or disable CONFIG_SYSFS_DEPRECATED;
	some udev features will not work correctly

and sure enough, turning off SYSFS_DEPRECATED brings the login prompt back.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>