meta-ibm: Configure tacoma machine for new u-boot

This selects the ast2600 openbmc u-boot configuration and the tacoma
device tree.

(From meta-ibm rev: b36b9ebc7f25a7d86d5c0e1cec81f156633921bd)

Change-Id: I079fc3d82ae1a453719923c743f58dd2c529968d
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/meta-ibm/meta-witherspoon/conf/machine/witherspoon-tacoma.conf b/meta-ibm/meta-witherspoon/conf/machine/witherspoon-tacoma.conf
index a57d142..765c068 100644
--- a/meta-ibm/meta-witherspoon/conf/machine/witherspoon-tacoma.conf
+++ b/meta-ibm/meta-witherspoon/conf/machine/witherspoon-tacoma.conf
@@ -1,5 +1,6 @@
 KERNEL_DEVICETREE = "aspeed-bmc-opp-tacoma.dtb"
-UBOOT_MACHINE = "evb-ast2600_defconfig"
+UBOOT_MACHINE = "ast2600_openbmc_defconfig"
+UBOOT_DEVICETREE = "ast2600-tacoma"
 
 IMAGE_FSTYPES += "ext4"