Enable CONFIG_OF for the overlays of dts.

Change-Id: I7d290792c520c5d8a90c94cf14e6f2b89911fbaf
Signed-off-by: yi-hsin_hung <yi-hsin_hung@asus.com>

Author: yihsin-hung

arch/arm/configs/miniarm-rk3288_defconfig

@@ -359,6 +359,18 @@ CONFIG_ZRAM=y
 CONFIG_BLK_DEV_LOOP=y
 CONFIG_BLK_DEV_RAM=y
 CONFIG_BLK_DEV_RAM_COUNT=1
+CONFIG_OF=y
+CONFIG_OF_UNITTEST=y
+CONFIG_OF_FLATTREE=y
+CONFIG_OF_EARLY_FLATTREE=y
+CONFIG_OF_DYNAMIC=y
+CONFIG_OF_ADDRESS=y
+CONFIG_OF_IRQ=y
+CONFIG_OF_NET=y
+CONFIG_OF_MDIO=y
+CONFIG_OF_RESERVED_MEM=y
+CONFIG_OF_RESOLVE=y
+CONFIG_OF_OVERLAY=y
 CONFIG_SCSI=y
 CONFIG_BLK_DEV_SD=y
 CONFIG_BLK_DEV_SR=y