Allow customizing the framebuffer FPS.

src/Linux/Avalonia.LinuxFramebuffer/LinuxFramebufferPlatform.cs

@@ -37,15 +37,17 @@ namespace Avalonia.LinuxFramebuffer
             Threading = new InternalPlatformThreadingInterface();
             if (_fb is IGlOutputBackend gl)
                 AvaloniaLocator.CurrentMutable.Bind<IPlatformOpenGlInterface>().ToConstant(gl.PlatformOpenGlInterface);
+            
+            var opts = AvaloniaLocator.Current.GetService<LinuxFramebufferPlatformOptions>();
+            
             AvaloniaLocator.CurrentMutable
                 .Bind<IPlatformThreadingInterface>().ToConstant(Threading)
-                .Bind<IRenderTimer>().ToConstant(new DefaultRenderTimer(60))
+                .Bind<IRenderTimer>().ToConstant(new DefaultRenderTimer(opts?.Fps ?? 60))
                 .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<ICursorFactory>().ToTransient<CursorFactoryStub>()
                 .Bind<IKeyboardDevice>().ToConstant(new KeyboardDevice())
                 .Bind<IPlatformSettings>().ToSingleton<PlatformSettings>()
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>();
-
         }
 
        

src/Linux/Avalonia.LinuxFramebuffer/LinuxFramebufferPlatformOptions.cs

@@ -0,0 +1,14 @@
+namespace Avalonia.LinuxFramebuffer
+{
+    /// <summary>
+    /// Platform-specific options which apply to the Linux framebuffer.
+    /// </summary>
+    public class LinuxFramebufferPlatformOptions
+    {
+        /// <summary>
+        /// Gets or sets the number of frames per second at which the renderer should run.
+        /// Default 60.
+        /// </summary>
+        public int Fps { get; set; } = 60;
+    }
+}