Handle passing of extra file list to buildstrap

Previously we use base64, but it doesn't really work. For now just do a
silly temp file write and delete.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>

androdeb

@@ -198,9 +198,12 @@ if [[ $EUID -ne 0 ]]; then echo "The next stage runs as sudo, please enter passw
 
 SKIP_COMPRESS=0; if [ ! -z "$BUILD_IMAGE" ]; then SKIP_COMPRESS=1; fi
 
+ex_files=$(mktemp); echo $EXTRA_FILES > $ex_files
+
 sudo $spath/buildstrap $ARCH $DISTRO $TDIR $OUT_TMP \
 		"$(make_csv "$PACKAGES")"\
-		"$(echo "$EXTRA_FILES" | base64)" $INSTALL_BCC $SKIP_COMPRESS
+		$ex_files $INSTALL_BCC $SKIP_COMPRESS
+rm $ex_files
 
 # If we only wanted to prepare a rootfs and don't have
 # a device connected, then just echo that and skip cleanup

buildstrap

@@ -9,7 +9,7 @@ DISTRO=$2
 TDIR=$3
 OUT_TMP=$4
 PACKAGES=$5
-EXTRA_FILES=$(echo $6 | base64 -d)
+EXTRA_FILES="$(cat $6)"
 INSTALL_BCC=$7
 SKIP_COMPRESS=$8