u-boot-sdk: Use OpenBMC fork

This is a fork that is based on ASPEED's 2019.04 SDK fork. The goal is
to move to a mainline based tree, but while that work is underway, this
allows ast2600 support to move forward.

This gains support for NC-SI, and uses kconfig for the default
boot command allowing us to drop the patch to aspeed-common.h.

Machines will need to indicate which device tree to use. If possible we
should look to having a few common device trees, but for now they are
machine specific. The AST2600 is configured to use the ast2600a1-evb
device tree, which will also work on the a0 variant.

(From meta-aspeed rev: 22ccf4648a776c458300c97a6d001a843b2b5c9b)

Change-Id: Ib21dc9962761aac3f3148fe4908439b975545e1e
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/meta-aspeed/recipes-bsp/u-boot/u-boot-aspeed-sdk_2019.04.bb b/meta-aspeed/recipes-bsp/u-boot/u-boot-aspeed-sdk_2019.04.bb
index fe85338..4910685 100644
--- a/meta-aspeed/recipes-bsp/u-boot/u-boot-aspeed-sdk_2019.04.bb
+++ b/meta-aspeed/recipes-bsp/u-boot/u-boot-aspeed-sdk_2019.04.bb
@@ -1,6 +1,6 @@
 require u-boot-common-aspeed-sdk_${PV}.inc
 
-UBOOT_MAKE_TARGET ?= "u-boot.${UBOOT_SUFFIX}"
+UBOOT_MAKE_TARGET ?= "u-boot.${UBOOT_SUFFIX} DEVICE_TREE=${UBOOT_DEVICETREE}"
 
 require recipes-bsp/u-boot/u-boot.inc