video: Update video_set_default_colors() to support invert

It is useful to be able to invert the colours in some cases so that the
text matches the background colour. Add a parameter to the function to
support this.

It is strange that function takes a private data structure from another
driver as an argument. It seems better to pass the device and have the
function internally work out how to find its required information.

Signed-off-by: Simon Glass <sjg@chromium.org>

include/video.h

@@ -191,9 +191,10 @@ void video_set_flush_dcache(struct udevice *dev, bool flush);
 /**
  * Set default colors and attributes
  *
- * @priv	device information
+ * @dev:	video device
+ * @invert	true to invert colours
  */
-void video_set_default_colors(struct video_priv *priv);
+void video_set_default_colors(struct udevice *dev, bool invert);
 
 #endif /* CONFIG_DM_VIDEO */