drm/vblank: Pass crtc_id to page_flip_ioctl.

drm/vblank: Pass crtc_id to page_flip_ioctl.

We added crtc_id to the atomic ioctl, but forgot to add it for vblank
and page flip events. Commit bd386e518056 ("drm: Reorganize
drm_pending_event to support future event types [v2]") added it to
the vblank event, but page flip event was still missing.

Correct this and add a test for making sure we always set crtc_id correctly.

Fixes: bd386e518056 ("drm: Reorganize drm_pending_event to support future event types [v2]")
Fixes: 5db06a8a98f5 ("drm: Pass CRTC ID in userspace vblank events")
Cc: Daniel Stone <daniels@collabora.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.12+
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #irc
Testcase: igt/kms_vblank/crtc_id
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171123103737.47138-1-maarten.lankhorst@linux.intel.com