Fix startup failure on openwrt issue

package/openwrt/files/etc/init.d/smartdns

@@ -1,7 +1,7 @@
 #!/bin/sh /etc/rc.common
 # Copyright (C) 2018 Nick Peng (pymumu@gmail.com)
 
-START=50
+START=90
 SERVICE_USE_PID=1
 SERVICE_WRITE_PID=1
 SERVICE_DAEMONIZE=1
@@ -68,6 +68,8 @@ start_service() {
 	conf_append "bind" "[::]:$port"
 	SMARTDNS_PORT="$port"
 
+	mkdir -p $(dirname $SMARTDNS_CONF)
+
 	config_get "cache_size" "$section" "cache_size" ""
 	if [ ! -z "$cache_size" ]; then
 		conf_append "cache-size" "$cache_size"