build_image,cros_make_image_bootable: fix missing arm argument

bin/cros_make_image_bootable

 #!/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.
 #
 # Script which ensures that a given image has an up-to-date
 # kernel partition, rootfs integrity hashes, and legacy bootloader configs.
 
 # Load common constants.  This should be the first executable line.
@@ skipping 62 matching lines @@
   "Default all bootloaders to use kernel-based root fs integrity checking."
 DEFINE_integer verity_error_behavior 2 \
   "Kernel verified boot error behavior (0: I/O errors, 1: reboot, 2: nothing)"
 DEFINE_integer verity_depth 1 \
   "Kernel verified boot hash tree depth"
 DEFINE_integer verity_max_ios 1024 \
   "Number of outstanding I/O operations dm-verity caps at."
 DEFINE_string verity_algorithm "sha1" \
   "Cryptographic hash algorithm used for kernel vboot."
 
+DEFINE_string arm_extra_bootargs "" \
+  "Additional command line options to pass to the ARM kernel."
+
 DEFINE_string keys_dir "/usr/share/vboot/devkeys" \
   "Directory containing the signing keys."
 
 DEFINE_string rootfs_mountpoint "/tmp/rootfs" \
   "Path where the rootfs can be safely mounted"
 DEFINE_string statefulfs_mountpoint "/tmp/statefulfs" \
   "Path where the statefulfs can be safely mounted"
 DEFINE_string espfs_mountpoint "/tmp/espfs" \
   "Path where the espfs can be safely mounted"
 
@@ skipping 151 matching lines @@
 mkdir -p ${FLAGS_statefulfs_mountpoint}
 mkdir -p ${FLAGS_espfs_mountpoint}
 
 make_image_bootable ${IMAGE}
 
 if [ ${FLAGS_cleanup_dirs} -eq ${FLAGS_TRUE} ]; then
   rmdir ${FLAGS_rootfs_mountpoint}
   rmdir ${FLAGS_statefulfs_mountpoint}
   rmdir ${FLAGS_espfs_mountpoint}
 fi