powerpc: dts: Enable device tree support for T2080QDS

Add device tree for T2080QDS board and enable CONFIG_OF_CONTROL
so that device tree can be compiled.

Update board README for device tree usage.

Signed-off-by: Jagdish Gediya <jagdish.gediya@nxp.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/configs/T2080QDS_NAND_defconfig b/configs/T2080QDS_NAND_defconfig
index 6b5de4d..4a39cd2 100644
--- a/configs/T2080QDS_NAND_defconfig
+++ b/configs/T2080QDS_NAND_defconfig
@@ -7,6 +7,7 @@
 CONFIG_SPL=y
 CONFIG_MPC85xx=y
 CONFIG_TARGET_T2080QDS=y
+CONFIG_DEFAULT_DEVICE_TREE="t2080qds"
 CONFIG_FIT=y
 CONFIG_FIT_VERBOSE=y
 CONFIG_OF_BOARD_SETUP=y
@@ -35,6 +36,7 @@
 CONFIG_CMD_MTDPARTS=y
 CONFIG_MTDIDS_DEFAULT="nor0=fe8000000.nor,nand0=fff800000.flash,spi0=spife110000.0"
 CONFIG_MTDPARTS_DEFAULT="mtdparts=fe8000000.nor:1m(uboot),5m(kernel),128k(dtb),96m(fs),-(user);fff800000.flash:1m(uboot),5m(kernel),128k(dtb),96m(fs),-(user);spife110000.0:1m(uboot),5m(kernel),128k(dtb),-(user)"
+CONFIG_OF_CONTROL=y
 CONFIG_ENV_IS_IN_NAND=y
 CONFIG_FSL_CAAM=y
 CONFIG_FSL_ESDHC=y
@@ -54,4 +56,3 @@
 CONFIG_FSL_ESPI=y
 CONFIG_USB=y
 CONFIG_USB_STORAGE=y
-CONFIG_OF_LIBFDT=y