meson: kmsro: require dri3 for X11

meson: kmsro: require dri3 for X11

The current implementation in kmsro relies on buffer sharing using
WINSYS_HANDLE_TYPE_FD, which in x11 is only used by default when dri3
is enabled.
Since the current implementation will not work without it, we can
prevent user error by checking that it is not disabled at configuration
time.

Closes #4861

Signed-off-by: Erico Nunes <nunes.erico@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11305>