sane: added systemd build option.

srcpkgs/sane/template

@@ -1,7 +1,7 @@
 # Template build file for 'sane'.
 pkgname=sane
 version=1.0.24
-revision=6
+revision=7
 wrksrc="sane-backends-${version}"
 build_style=gnu-configure
 configure_args="--disable-locking --enable-avahi --disable-latex --enable-ipv6
@@ -10,7 +10,6 @@ hostmakedepends="pkg-config"
 makedepends="avahi-libs-devel libjpeg-turbo-devel tiff-devel libgphoto2-devel
  v4l-utils-devel libusb-devel net-snmp-devel libieee1284-devel libressl-devel cups-devel"
 depends="net-snmp sane-udev-rules"
-systemd_services="saned.socket on"
 conf_files="
 	/etc/sane.d/abaton.conf
 	/etc/sane.d/agfafocus.conf
@@ -96,14 +95,21 @@ license="GPL-2"
 distfiles="http://ftp.lfs-matrix.net/pub/blfs/conglomeration/sane-backends/sane-backends-${version}.tar.gz"
 checksum=27c7085a54f1505d8b551e6f1e69d30e1ee57328b18429bb2225dabf4c45462d
 
+build_options="systemd"
+if [ "$build_option_systemd" ]; then
+	systemd_services="saned.socket on"
+fi
+
 post_install() {
 	# fix hp officejets
 	echo "#hpaio" >> ${DESTDIR}/etc/sane.d/dll.conf
 	# Install systemd service.
+	if [ "$build_option_systemd" ]; then
 		vinstall ${FILESDIR}/saned@.service 644 usr/lib/systemd/system
 		vinstall ${FILESDIR}/saned.socket 644 usr/lib/systemd/system
-	vinstall ${FILESDIR}/saned.xinetd 644 etc/xinetd.d saned.conf
+	fi
 
+	vinstall ${FILESDIR}/saned.xinetd 644 etc/xinetd.d saned.conf
 	vinstall ${wrksrc}/tools/sane-backends.pc 644 usr/lib/pkgconfig
 
 	if [ -z "$CROSS_BUILD" ]; then