make_dev_firmware: new script to change firmware to dev key

scripts/image_signing/common.sh

 #!/bin/bash
 
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Determine script directory
 SCRIPT_DIR=$(dirname $0)
 PROG=$(basename $0)
 GPT=cgpt
 
 # The tag when the rootfs is changed.
 TAG_NEEDS_TO_BE_SIGNED="/root/.need_to_be_signed"
 
 # Load shflags
-if [[ -f /usr/lib/shflags ]]; then
+if [ -f /usr/lib/shflags ]; then
   . /usr/lib/shflags
 else
   . "${SCRIPT_DIR}/lib/shflags/shflags"
 fi
 
 # List of Temporary files and mount points.
 TEMP_FILE_LIST=$(mktemp)
 TEMP_DIR_LIST=$(mktemp)
 
 # Read GPT table to find the starting location of a specific partition.
@@ skipping 117 matching lines @@
       sudo umount -d $i 2>/dev/null
       rm -rf $i
     fi
   done
   set -e
   rm -rf $TEMP_DIR_LIST $TEMP_FILE_LIST
 }
 
 trap "cleanup_temps_and_mounts" EXIT