The recent addition of support for multi-frame (non-animation) formats
had an unwanted side effect of sometimes calling
QImageReader::nextImageDelay() when the reader is at a different
frame than intended. Fix by effectively reverting to the previous call
pattern.
Fixes: QTBUG-124227
Pick-to: 6.7 6.5
Change-Id: I735f8d67afb17bd4c77f9b4507a71796b7d66958
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>
5f0ed0ac0d