Add u-boot redundant environments

Update fw_env config with two sections.
Update init script to handle redundant envs.
Patch u-boot. Can be removed when openbmc/u-boot is updated and recipe
bumped.

Resolves openbmc/openbmc#1937

Change-Id: I15137f55d960381a0b3fbb58c53090bbd5b86482
Signed-off-by: Edward A. James <eajames@us.ibm.com>
diff --git a/common/recipes-bsp/u-boot/u-boot.inc b/common/recipes-bsp/u-boot/u-boot.inc
index 4c5e302..492e3f7 100644
--- a/common/recipes-bsp/u-boot/u-boot.inc
+++ b/common/recipes-bsp/u-boot/u-boot.inc
@@ -5,3 +5,5 @@
 SRC_URI = "git://git@github.com/openbmc/u-boot.git;branch=${UBRANCH};protocol=https"
 
 PV = "v2016.07+git${SRCPV}"
+
+SRC_URI += "file://0001-configs-ast-Add-redundnant-env.patch"