Add option to change controller LED color (#572)

This allows the user to change the controller LED while using Ryujinx.
Useful for PS4 and PS5 controllers as an example.

You can also use a spectrum-cycling Rainbow color option, or turn the LED off for DualSense controllers.

---------

Co-authored-by: Evan Husted <greem@greemdev.net>

src/Ryujinx.SDL2.Common/SDL2Driver.cs

@@ -1,5 +1,6 @@
 using Ryujinx.Common.Configuration;
 using Ryujinx.Common.Logging;
+using Ryujinx.Common.Utilities;
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -167,6 +168,8 @@ namespace Ryujinx.SDL2.Common
                         HandleSDLEvent(ref evnt);
                     }
                 });
+                
+                Rainbow.Tick();
 
                 waitHandle.Wait(WaitTimeMs);
             }