[Intel-gfx] [PATCH i-g-t] tests/kms_flip: fix spin_batch conversion

[Chris Wilson]

Quoting Daniel Vetter (2017-08-14 21:32:00)
> The goal of these subtests was just to delay a kms operation a little
> bit. The goal wasn't to
> - spin until the operation was completed. That results in a gpu hang,
>   and gpu hangs need igt_hang for safety.
> - complete it before the operation. That's just pointless.

It didn't use the arbitrary timeout to avoid the race condition of it
finishing before the flip was queued.
 
> Fix it by using the timeout support.

Find the path that was broken and fix it. At a guess just the pair of
TEST_DPMS need to consider how exactly they want to interact with the
busy fb.
-Chris