powerpc/mpc5121: drop "select MPC5121_ADS_CPLD"

There is no Kconfig symbol named MPC5121_ADS_CPLD. The select statement
for that symbol is a nop. Drop it.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

arch/powerpc/platforms/512x/Kconfig

@@ -12,7 +12,6 @@ config MPC5121_ADS
 	bool "Freescale MPC5121E ADS"
 	depends on PPC_MPC512x
 	select DEFAULT_UIMAGE
-	select MPC5121_ADS_CPLD
 	help
 	  This option enables support for the MPC5121E ADS board.