Fix board lookup code to work from any directory.

src/scripts/autotest_lib.sh

 # 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.
 #
 # Provides common commands for dealing running/building autotest
 
 . "$(dirname "$0")/common.sh"
 
 get_default_board
 
 DEFINE_string board "$DEFAULT_BOARD" \
     "The board for which you are building autotest"
 
 function check_board() {
   local board_names=""
   local index=1
   local found=0
-  for board in ../overlays/overlay-*
+  for overlay_path in "${SRC_ROOT}"/overlays/overlay-*
   do
-    board_names[index]=${board:20}
+    local overlay="$(basename \"${overlay_path}\")"
+    local board="${overlay#overlay-}"
+    board_names[index]="${board}"
     index+=1
-    if [ "${FLAGS_board}" == "${board:20}" ]
+    if [ "${FLAGS_board}" == "${board}" ]
     then
       found=1
     fi
   done
 
   if [ ${found} -eq 0 ]
   then
     echo "You are required to specify a supported board from the command line."
     echo "Supported boards are:"
     for board in ${board_names[@]}
@@ skipping 11 matching lines @@
 #   $1 - original source directory
 #   $2 - target directory
 function update_chroot_autotest() {
   local original=$1
   local target=$2
   echo "Updating chroot Autotest from ${original} to ${target}..."
   sudo mkdir -p "${target}"
   sudo chmod 777 "${target}"
   cp -fpru ${original}/{client,conmux,server,tko,utils,global_config.ini,shadow_config.ini} ${target}
 }