Use commit number instead of autorev for u-boot

Change the u-boot recipes from picking up the most recent
commit to a specific commit (the most current one a of today)
so that development can be done in u-boot without affecting the
stability of the image.
diff --git a/common/recipes-bsp/u-boot/u-boot-fw-utils_2013.07.bb b/common/recipes-bsp/u-boot/u-boot-fw-utils_2013.07.bb
index c8ae846..bfbdcf6 100644
--- a/common/recipes-bsp/u-boot/u-boot-fw-utils_2013.07.bb
+++ b/common/recipes-bsp/u-boot/u-boot-fw-utils_2013.07.bb
@@ -12,7 +12,7 @@
 # We use the revision in order to avoid having to fetch it from the
 # repo during parse
 # SRCREV = "62c175fbb8a0f9a926c88294ea9f7e88eb898f6c"
-SRCREV="${AUTOREV}"
+SRCREV="4b44678c11ac82c7c797bb115e276181752ad54d"
 
 PV = "v2013.07+git${SRCPV}"
 
diff --git a/common/recipes-bsp/u-boot/u-boot_2013.07.bb b/common/recipes-bsp/u-boot/u-boot_2013.07.bb
index 80715e7..6070fbf 100644
--- a/common/recipes-bsp/u-boot/u-boot_2013.07.bb
+++ b/common/recipes-bsp/u-boot/u-boot_2013.07.bb
@@ -12,7 +12,7 @@
 
 # This revision corresponds to the tag "v2013.07"
 # We use the revision in order to avoid having to fetch it from the repo during parse
-SRCREV = "${AUTOREV}"
+SRCREV = "4b44678c11ac82c7c797bb115e276181752ad54d"
 
 PV = "v2013.07+git${SRCPV}"