Enable high DPI pixmaps
Summary:
Enable High DPI pixmaps to make icons in dialogs looks nice
if High DPI is enabled.
BUG: 407726
Test Plan: Checked manually in high DPI environment.
Reviewers: hein, cfeck, ngraham
Reviewed By: cfeck, ngraham
Subscribers: ngraham
Differential Revision: https://phabricator.kde.org/D25038