[Development] Maintainers, your action needed: Qt 5.12.5 changes files

[Jani Heikkinen]

Hi,

Initial ones here: https://codereview.qt-project.org/q/message:%2522Add+changes+file+for+Qt+5.12.5%2522

Maintainers, please do needed modifications & make sure changes will be approved during this week.

br,
Jani Heikkinen
Release Manager