Fix SpriteIcon loading textures on the update thread

osu.Game/Graphics/SpriteIcon.cs

@@ -57,11 +57,6 @@ namespace osu.Game.Graphics
         private void load(FontStore store)
         {
             this.store = store;
-        }
-
-        protected override void LoadComplete()
-        {
-            base.LoadComplete();
 
             updateTexture();
         }