The mac heic handler lacked support for any meta-data i/o. Most
notably, the image orientation proprty was ignored, so images read in
could be wrongly oriented.

Fixes: QTBUG-73415
Change-Id: I779f91dc28c7441b124aab4557e1abcd3e69fde9
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>