Revert r496041 and r496054.
The changes were right, but they broke `make configure' in ports that have
USE_KDE=wayland because now both Mk/Uses/qt.mk and Mk/Uses/kde.mk set
wayland_PORT and wayland_LIB, and qt.mk's version overrides kde.mk's. This
means we will end up installing graphics/qt5-wayland rather than
CMake Error at CMakeLists.txt:27 (find_package):
Could not find a package configuration file provided by "KF5Wayland" (requested version 5.54.0) with any of the following names: KF5WaylandConfig.cmake kf5wayland-config.cmake Add the installation prefix of "KF5Wayland" to CMAKE_PREFIX_PATH or set "KF5Wayland_DIR" to a directory containing one of the above files. If "KF5Wayland" provides a separate development package or SDK, be sure it has been installed.
Bump PORTREVISION in x11/kf5-plasma-framework, it has an optional dependency on
kf5-kwayland and was thus building fine despite the wrong dependencies.