kwayland-integration: fix compilation with no-deprecated build of kwindowsystem
Summary:
I build kwindowsystem with -DEXCLUDE_DEPRECATED_BEFORE_AND_AT=5.62.0,
and this broke here. Use the exact same condition as the one around
those virtual methods in the base class.
This required upgrading the KF5 requirement from 5.62 to 5.64,
so no backport to Plasma/5.17 unfortunately.
Reviewers: kossebau, jriddell, davidedmundson
Reviewed By: kossebau
Subscribers: plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D25488