Log Message:
sysutils/pcmanfm-qt: update to 2.0.0

pcmanfm-qt-2.0.0 (2024-04-17)
 - Ported to Qt6.
 - Used layer-shell-qt for Desktop under Wayland.
 - Fixed rare misplacement of desktop icons with Qt6.
 - Added 5 menu icons to the main window.
 - Disabled root instance under Wayland.

pkgsrc: layer-shell-qt from Plasma 6 is only needed under Wayland, disable this
requirement for now.