[PATCH] drm: Revert "add syncobj timeline support v9"

[Chris Wilson]

Quoting Christian König (2018-10-19 10:27:11)
> From: Christian König <easy2remember.chk at googlemail.com>
> 
> Still contains some bugs.
> 
> This reverts commit 48197bc564c7a1888c86024a1ba4f956e0ec2300.
> 
> Bugs: https://bugs.freedesktop.org/show_bug.cgi?id=108490
> Signed-off-by: Christian König <Christian.Koenig at amd.com>

The code for the old style of syncobj == dma_fence is very very slow, as
now instead of using the syncobj as an idr to the fence, we must always
search a linked list. A major regression for existing behaviour.
-Chris