Document that wrap modes do not work with atlas textures

Change-Id: Ifa417644e10b947c4ca0b9c518cfd800b63142b5
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>

src/quick/scenegraph/util/qsgtexture.cpp

@@ -256,6 +256,8 @@ static void qt_debug_remove_texture(QSGTexture* texture)
 
     Specifies how the texture should treat texture coordinates.
 
+    \note Texture wrapping needs to be handled explicitly for atlas textures.
+
     \value Repeat Only the factional part of the texture coordiante is
     used, causing values above 1 and below 0 to repeat.