[GUI] Add network interface dropdown (#4597)

* Add network adapter dropdown from LDN build

* Ava: Add NetworkInterfaces to SettingsNetworkTab

* Add headless network interface option

* Add network interface dropdown to Avalonia

* Fix handling network interfaces without a gateway address

* gtk: Actually save selected network interface to config

* Increment config version

Ryujinx.Headless.SDL2/Program.cs

@@ -548,7 +548,8 @@ namespace Ryujinx.Headless.SDL2
                                                                   options.IgnoreMissingServices,
                                                                   options.AspectRatio,
                                                                   options.AudioVolume,
-                                                                  options.UseHypervisor);
+                                                                  options.UseHypervisor,
+                                                                  options.MultiplayerLanInterfaceId);
 
             return new Switch(configuration);
         }