dhcpcd: add systemd start-up service

Add systemd start-up configuration for dhcpcd that is executed after
the network has been brought up.

Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/dhcpcd/dhcpcd.mk

@@ -41,6 +41,14 @@ define DHCPCD_INSTALL_INIT_SYSV
 		$(TARGET_DIR)/etc/init.d/S41dhcpcd
 endef
 
+define DHCPCD_INSTALL_INIT_SYSTEMD
+	$(INSTALL) -D -m 0644 package/dhcpcd/dhcpcd.service \
+		$(TARGET_DIR)/usr/lib/systemd/system/dhcpcd.service
+	mkdir -p $(TARGET_DIR)/etc/systemd/system/multi-user.target.wants
+	ln -sf ../../../../usr/lib/systemd/system/dhcpcd.service \
+		$(TARGET_DIR)/etc/systemd/system/multi-user.target.wants/dhcpcd.service
+endef
+
 # NOTE: Even though this package has a configure script, it is not generated
 # using the autotools, so we have to use the generic package infrastructure.
 

package/dhcpcd/dhcpcd.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=DHCP client
+After=network.target
+
+[Service]
+Type=forking
+EnvironmentFile=-/etc/default/dhcpcd
+PIDFile=/var/run/dhcpcd.pid
+ExecStart=/sbin/dhcpcd $DAEMON_ARGS
+Restart=always
+
+[Install]
+WantedBy=multi-user.target