GitLab

Implement sync_file export for fences so we can submit fences with planes
to DRM atomic.

This does not work unless you have a fairly recent kernel (requires
syncobj support, I915_EXEC_FENCE_ARRAY).

Bug: 851997
Test: ozone_demo on eve with USE=vulkan and kernel 4.14

Change-Id: I5859b64690e9b45ccb95698a9ca096f0847ec51b
Reviewed-on: https://chromium-review.googlesource.com/1115570Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: Michael Spang <spang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572262}