Add tap-button-map and tap-drag-lock touchpad libinput settings for X11 and Wayland
Gnome now misses two libinput touchpad settings:
- tap button mapping
- tap dragging lock
This commit enables those two features in mutter for both X11 and Wayland. It has to be tested against this merge request which includes the relative keys in gsettings.
Already tested on my Arch Linux system, it's working.