Only RGB444 and RGB666 were treated slighlty different from the rest, but the test had a few additional mistakes. Pick-to: 6.1 6.0 5.15 Change-Id: I4728b4036affedfffce8bca5c1e7be3869344fbe Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>