xwayland: add -noTouchPointerEmulation

In some scenarios, the Wayland compositor might have more knowledge
than the X11 server and may be able to perform pointer emulation for
touch events better. Add a command-line switch to allow compositors
to turn Xwayland pointer emulation off.

Signed-off-by: Simon Ser <contact@emersion.fr>
5 jobs for no-touch-emulate-pointer in 7 minutes and 14 seconds (queued for 5 seconds)