Disable the systemd option by default in all packages.

srcpkgs/gvfs/template

@@ -1,7 +1,7 @@
 # Template file for 'gvfs'
 pkgname=gvfs
 version=1.20.2
-revision=3
+revision=4
 build_style=gnu-configure
 configure_args="--disable-hal --disable-afc
  --with-bash-completion-dir=/usr/share/bash-completion/completions"
@@ -21,7 +21,6 @@ checksum=84d9412e7bedfba902696ae7fb0cfceb0b66b98823f8388745b20693e3b24f8e
 
 # Package build options
 build_options="systemd"
-build_options_default="systemd"
 
 if [ "$build_option_systemd" ]; then
 	configure_args+=" --enable-systemd"