firmware: mark auf-feindgebiet.de as Cloudflare CDN

This is a pretty good option for anybody with a lack of a viable
local mirror, sparked by talks of a South-East Asia region mirror.

(cherry picked from commit 5b4acfac)

src/opnsense/mvc/app/controllers/OPNsense/Core/Api/FirmwareController.php

@@ -588,7 +588,7 @@ class FirmwareController extends ApiControllerBase
         $mirrors[''] = '(default)';
         $mirrors['https://opnsense.aivian.org'] = 'Aivian (Shaoxing, CN)';
         $mirrors['https://opnsense-update.deciso.com'] = 'Deciso (NL, Commercial)';
-        $mirrors['https://mirror.auf-feindgebiet.de/opnsense'] = 'auf-feindgebiet.de (Karlsruhe, DE)';
+        $mirrors['https://mirror.auf-feindgebiet.de/opnsense'] = 'auf-feindgebiet.de (Cloudflare CDN)';
         $mirrors['https://opnsense.c0urier.net'] = 'c0urier.net (Lund, SE)';
         //$mirrors['https://fleximus.org/mirror/opnsense'] = 'Fleximus (Roubaix, FR)';
         $mirrors['https://fourdots.com/mirror/OPNSense'] = 'FourDots (Belgrade, RS)';