[PATCH wayland-protocols] presentation-time: add missing bitfield marker

[Simon Ser]

That's a good catch.

However I don't know if this can be considered backwards-compatible.
For wayland-scanner it doesn't make a difference, but what about other
scanners?

The commit introducing bitfields in the DTD predates presentation-time.

commit e65aed46168fc86a7e78db071472278ea533f526
Author: Peter Hutterer <peter.hutterer at who-t.net>
Date:   Tue Nov 10 09:34:32 2015 +1000

    protocol: add the new bitfields to the dtd

    See 851614fa78862499e016c5718e730fefbb8e3b73

commit 95e7f445edbc8ea52b6f4d22ae1ee514b2323895
Author: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
Date:   Wed Feb 17 16:32:05 2016 +0200

    stable: add presentation-time draft

    This XML file has been copied verbatim from Weston 1.10.0 release,
    protocol/presentation_timing.xml. The last behavioral change to that
    file was in December 2014, so the behaviour is considered stable.

    Interfaces still need to be renamed according wayland-protocols policy.
    That will be done in a follow-up patch to clearly show the changes.