u-boot : add fw_env.config

Add the fw_env.config file to SRC_URI to include it in the build
tree, and update it to point to /dev/mtd2 as 128k, which the
current flash layout.

Signed-off-by: Milton Miller <miltonm@us.ibm.com>
diff --git a/meta-ast2400/recipes-bsp/u-boot/u-boot_2013.07%.bbappend b/meta-ast2400/recipes-bsp/u-boot/u-boot_2013.07%.bbappend
index 12fddbf..50adb9f 100644
--- a/meta-ast2400/recipes-bsp/u-boot/u-boot_2013.07%.bbappend
+++ b/meta-ast2400/recipes-bsp/u-boot/u-boot_2013.07%.bbappend
@@ -1,5 +1,6 @@
 FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
 
+SRC_URI += "file://fw_env.config"
 SRC_URI += "file://config.patch"
 
 # Do not install u-boot in rootfs