Fixed sign_official_build.sh to work with PARTUUID

Fixed sign_official_build.sh to work with PARTUUID in the linux format,
PARTUUID=%U/PARTNROFF=1. Had to handle the '/'.

Also fixed a misspelled variable name, devcie -> device. It worked
before because a NULL string generated the right results in the
current configuration.

BUG=chromium:224066
TEST=~/trunk/src/platform/vboot_reference/scripts/image_signing/sign_official_build.sh recovery /home/taysom/trunk/src/build/images/$B/latest/recovery_image.bin /home/taysom/trunk/src/platform/vboot_reference/tests/devkeys /tmp/taysom.bin
BRANCH=none

Change-Id: Id201885a63c6eba4cdb7c9216c0d3d35e6d3f0c4
Reviewed-on: https://gerrit.chromium.org/gerrit/61889
Tested-by: Paul Taysom <taysom@chromium.org>
Reviewed-by: Gaurav Shah <gauravsh@chromium.org>
Commit-Queue: Paul Taysom <taysom@chromium.org>
diff --git a/scripts/image_signing/sign_official_build.sh b/scripts/image_signing/sign_official_build.sh
index 492dd15..53b9483 100755
--- a/scripts/image_signing/sign_official_build.sh
+++ b/scripts/image_signing/sign_official_build.sh
@@ -154,7 +154,7 @@
   local device=$2
   local slave=$3
   echo $(echo "${dm}" |
-    sed -nre "s/(.*${devcie}[^,]*,)([^,]*)(.*)/\1${slave}\3/p")
+    sed -nre "s#(.*${device}[^,]*,)([^,]*)(.*)#\1${slave}\3#p")
 }
 
 CALCULATED_KERNEL_CONFIG=