powerpc/p2020ds: Integrated with P2020DS DDR change and enabled hwconfig

Enabled SPD
Enabled DDR2
Enabled hwconfig

Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/Makefile b/Makefile
index 9cea069..4f1cb1b 100644
--- a/Makefile
+++ b/Makefile
@@ -1788,6 +1788,7 @@
 P2010RDB_NAND_config \
 P2010RDB_SDCARD_config \
 P2010RDB_SPIFLASH_config \
+P2020DS_DDR2_config \
 P2020RDB_config \
 P2020RDB_NAND_config \
 P2020RDB_SDCARD_config \