Driver/DDR: Moving Freescale DDR driver to a common driver

Freescale DDR driver has been used for mpc83xx, mpc85xx, mpc86xx SoCs.
The similar DDR controllers will be used for ARM-based SoCs.

Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/board/sbc8548/Makefile b/board/sbc8548/Makefile
index b1e32a6..4c9b6cd 100644
--- a/board/sbc8548/Makefile
+++ b/board/sbc8548/Makefile
@@ -11,4 +11,4 @@
 obj-y	+= sbc8548.o
 obj-y	+= law.o
 obj-y	+= tlb.o
-obj-$(CONFIG_FSL_DDR2) += ddr.o
+obj-$(CONFIG_SYS_FSL_DDR2) += ddr.o