drivers/misc/eeprom: fix dependecy on 'PPC_MPC5200_GPIO'

The driver for the DigsyMTC display configuration EEPROMs device got
added by commit 469dded1 ("misc/eeprom: add eeprom access driver for
digsy_mtc board").  Its Kconfig symbol depends on PPC_MPC5200_GPIO.  But
at the time that driver got added PPC_MPC5200_GPIO was already renamed
to GPIO_MPC5200, by commit 6eae1ace ("gpio: Move mpc5200 gpio driver
to drivers/gpio").

So make this driver depend on GPIO_MPC5200.  And since GPIO_MPC5200
itself implies that GPIOLIB is set, that dependency can be dropped.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Anatolij Gustschin <agust@denx.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>