proftpd: systemd support

[Thomas: change to use a relative symlink, and fix a minor typo in the
service file in the service description.]

Signed-off-by: Alex Suykov <alex.suykov@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/proftpd/proftpd.mk

@@ -55,4 +55,12 @@ define PROFTPD_INSTALL_INIT_SYSV
 	$(INSTALL) -D -m 0755 package/proftpd/S50proftpd $(TARGET_DIR)/etc/init.d/S50proftpd
 endef
 
+define PROFTPD_INSTALL_INIT_SYSTEMD
+	$(INSTALL) -D -m 644 package/proftpd/proftpd.service \
+		$(TARGET_DIR)/usr/lib/systemd/system/proftpd.service
+	mkdir -p $(TARGET_DIR)/etc/systemd/system/multi-user.target.wants
+	ln -sf ../../../../usr/lib/systemd/system/proftpd.service \
+		$(TARGET_DIR)/etc/systemd/system/multi-user.target.wants/proftpd.service
+endef
+
 $(eval $(autotools-package))

package/proftpd/proftpd.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=FTP server
+After=syslog.target network.target
+
+[Service]
+ExecStart=/usr/sbin/proftpd -n -q
+Restart=always
+
+[Install]
+WantedBy=multi-user.target