D21300: KIO: port away from QSslSocket+QFileInfo deprecated API

[Aleix Pol Gonzalez]

apol accepted this revision.
This revision is now accepted and ready to land.

REPOSITORY
  R241 KIO

BRANCH
  2019_deprecated_API

REVISION DETAIL
  https://phabricator.kde.org/D21300

To: dfaure, apol
Cc: kde-frameworks-devel, michaelh, ngraham, bruns