dbus: enable systemd support

Enable systemd support if systemd is selected as init system (require
systemd compatibility libraries).

Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/dbus/Config.in

@@ -4,6 +4,7 @@ config BR2_PACKAGE_DBUS
 	# uses fork()
 	depends on BR2_USE_MMU
 	select BR2_PACKAGE_EXPAT
+	select BR2_PACKAGE_SYSTEMD_COMPAT if BR2_INIT_SYSTEMD
 	help
 	  The D-Bus message bus system.
 

package/dbus/dbus.mk

@@ -50,8 +50,13 @@ else
 DBUS_CONF_OPT += --without-x
 endif
 
-ifeq ($(BR2_PACKAGE_SYSTEMD),y)
-DBUS_CONF_OPT += --with-systemdsystemunitdir=/lib/systemd/system
+ifeq ($(BR2_INIT_SYSTEMD),y)
+DBUS_CONF_OPT += \
+	--enable-systemd \
+	--with-systemdsystemunitdir=/lib/systemd/system
+DBUS_DEPENDENCIES += systemd
+else
+DBUS_CONF_OPT += --disable-systemd
 endif
 
 # fix rebuild (dbus makefile errors out if /var/lib/dbus is a symlink)