Allow the ability to turn off the LED entirely

Only works for DualSense; in my testing, my DualShock 4 ignored the requests to set the LED to off.

src/Ryujinx.Common/Configuration/Hid/Controller/LedConfigController.cs

@@ -2,14 +2,19 @@
 {
     public class LedConfigController
     {
-        /// <summary>
-        ///     Packed RGB int of the color
-        /// </summary>
-        public uint LedColor { get; set; }
-
         /// <summary>
         /// Enable LED color changing by the emulator
         /// </summary>
         public bool EnableLed { get; set; }
+        
+        /// <summary>
+        /// Ignores the color and disables the LED entirely.
+        /// </summary>
+        public bool TurnOffLed { get; set; }
+        
+        /// <summary>
+        ///     Packed RGB int of the color
+        /// </summary>
+        public uint LedColor { get; set; }
     }
 }