message: generate-pc.sh: add option to set libdir
diff: # ==============================================================================
  TF_PREFIX='/usr/local'
  +LIBDIR='lib'
  usage() {
  echo "Usage: $0 OPTIONS"
  echo -e "-p, --prefix\tset installation prefix (default: /usr/local)"
  + echo -e "-l, --libdir\tset lib directory (default: lib)"
  echo -e "-v, --version\tset TensorFlow version"
  echo -e "-h, --help\tdisplay this message"
  }
  @@ -26,7 +28,7 @@ usage() {
  [ $# == 0 ] && usage && exit 0
  # read the options
  -ARGS=$(getopt -o p:v:h --long prefix:,version:,help -n $0 -- "$@")
  +ARGS=$(getopt -o p:l:v:h --long prefix:,libdir:,version:,help -n $0 -- "$@")
  eval set -- "$ARGS"
  # extract options and their arguments into variables.
  @@ -38,6 +40,11 @@ while true ; do
  "") shift 2 ;;
  *) TF_PREFIX=$2 ; shift 2 ;;
  esac ;;
  + -l|--libdir)
  + case "$2" in
  + "") shift 2 ;;
  + *) LIBDIR=$2 ; shift 2 ;;
  + esac ;;
  -v|--version)
  case "$2" in
  "") shift 2 ;;
  @@ -55,7 +62,7 @@ echo "Generating pkgconfig file for TensorFlow $TF_VERSION in $TF_PREFIX"
  cat << EOF > tensorflow.pc
  prefix=${TF_PREFIX}
  exec_prefix=\${prefix}
  -libdir=\${exec_prefix}/lib
  +libdir=\${exec_prefix}/${LIBDIR}
  includedir=\${prefix}/include
  Name: TensorFlow
  