Move to u-boot v2016.07-aspeed-openbmc branch

This moves all machines to a new u-boot branch. The u-boot branch is
based on this month's upstream v2016.07 release, and contains cleanups
that get us closer to submitting upstream.

Importantly for the machine configurations, we now have four new
defconfigs that replace the previous targets:

 - ast_g4_ncsi_defconfig: ast2400 with NCSI networking
 - ast_g4_phy_defconfig: ast2400 with directly attached PHY networking
 - ast_g5_ncsi_defconfig: ast2500 with NCSI networking
 - ast_g5_phy_defconfig: ast2500 with directly attached PHY networking

We now support Firestone again with the ast_g4_phy_defconfig.

This commit updates all machines to the new branch and defconfig. It
also removes unused patches that were being made to u-boot, in the case
of barreleye (a patch to aspeednic.c) and palmetto (a modification to
the u-boot environment).

Change-Id: Ic4baf9ae0d5f4046e69cab99d54865771b01cd2a
Signed-off-by: Joel Stanley <joel@jms.id.au>
diff --git a/meta-witherspoon/conf/machine/witherspoon.conf b/meta-witherspoon/conf/machine/witherspoon.conf
index 19ada2a..36941a6 100644
--- a/meta-witherspoon/conf/machine/witherspoon.conf
+++ b/meta-witherspoon/conf/machine/witherspoon.conf
@@ -1,7 +1,7 @@
 KMACHINE = "aspeed"
 KERNEL_DEVICETREE = "${KMACHINE}-bmc-opp-${MACHINE}.dtb"
 
-UBOOT_MACHINE = "witherspoon_bmc_config"
+UBOOT_MACHINE = "ast_g5_ncsi_config"
 
 require conf/machine/include/ast2500.inc
 require conf/machine/include/obmc-bsp-common.inc