bcc: INSTALL_BCC needs to always be defined

Signed-off-by: Joel Fernandes <joel@joelfernandes.org>
diff --git a/buildstrap b/buildstrap
index 5eca01f..d4ae1fd 100755
--- a/buildstrap
+++ b/buildstrap
@@ -58,14 +58,15 @@
 echo "nameserver 4.2.2.2" > $OUT_TMP/etc/resolv.conf
 
 # Clone BCC if needed
-if [[ ! -z ${INSTALL_BCC+x} ]]; then
-git clone https://github.com/iovisor/bcc.git $TDIR/debian/bcc-master
-cp $spath/bcc/build-bcc.sh $TDIR/debian/bcc-master/; fi
+if [ $INSTALL_BCC -eq 1 ]; then
+	git clone https://github.com/iovisor/bcc.git $TDIR/debian/bcc-master
+	cp $spath/bcc/build-bcc.sh $TDIR/debian/bcc-master/;
+fi
 
 # Should be really do this?
 chmod -R 0777 $TDIR/
 
-if [ $SKIP_DEVICE -eq 1 ]; then exit 0; fi
+[ $SKIP_DEVICE -eq 0 ] || exit 0
 
 c_info "Compressing new filesystem to prepare to push to Android /data/androdeb/"
 tar -zcf $TDIR/deb.tar.gz -C $TDIR debian