igt/kms_frontbuffer_tracking: Show FBC status during the wait

Currently, we have a sporadic failure in the multidraw tests where it
sometimes fails to start FBC in a timely fashion (and at other times
works fine). Try to get a little more information as wait it is waiting
for by showing the fbc status at each stage.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
1 file changed