busybox: use <pkg>_INSTALL_INIT_SYSV mechanism

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/busybox/busybox.mk

@@ -218,8 +218,11 @@ define BUSYBOX_INSTALL_TARGET_CMDS
 		$(INSTALL) -m 0755 -D package/busybox/udhcpc.script \
 			$(TARGET_DIR)/usr/share/udhcpc/default.script; \
 	fi
-	$(BUSYBOX_INSTALL_MDEV_SCRIPT)
 	$(BUSYBOX_INSTALL_MDEV_CONF)
+endef
+
+define BUSYBOX_INSTALL_INIT_SYSV
+	$(BUSYBOX_INSTALL_MDEV_SCRIPT)
 	$(BUSYBOX_INSTALL_LOGGING_SCRIPT)
 	$(BUSYBOX_INSTALL_WATCHDOG_SCRIPT)
 endef