xwayland: fix -noTouchPointerEmulation

Passing -noTouchPointerEmulation results in an error about the
flag not being recognized.

Signed-off-by: Simon Ser <contact@emersion.fr>
Fixes: 7d34b1f2 ("xwayland: add -noTouchPointerEmulation")
5 jobs for no-touc-pointer-emu-flag in 5 minutes and 11 seconds (queued for 6 seconds)