Exit if directory change fails

src/freedombone-utils-elixir

@@ -78,11 +78,11 @@ function image_install_elixir {
     fi
 
     { echo '#!/bin/bash';
-      echo "cd $INSTALL_DIR";
+      echo "cd $INSTALL_DIR || exit 1";
       echo "erlang_package=$erlang_package";
       echo "wget https://packages.erlang-solutions.com/\$erlang_package";
       echo "if [ ! -f \"\$INSTALL_DIR/\$erlang_package\" ]; then";
-      echo '    exit 1';
+      echo '    exit 2';
       echo 'fi';
       echo "dpkg -i \$erlang_package"; } > "$rootdir/usr/bin/install_elixir"
     chmod +x "$rootdir/usr/bin/install_elixir"