Update firmware/openwrt redirect path to up-to-date mirror

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

nginx/firmware.srv.in.ffho.net

@@ -50,7 +50,7 @@ server {
 
 	# opkg mirror
 	location ~^/openwrt/(?<file>.+)$ {
-		return 302 http://ftp.stw-bonn.de/pub/openwrt/$file;
+		return 302 http://downloads.openwrt.org/releases/$file;
 	}
 
 	# lede mirror