broadcom/vc4: Native fence fd support
With the syncobj support in place, lets use it to implement the
EGL_ANDROID_native_fence_sync extension. This mostly follows previous
implementations in freedreno and etnaviv.
v2: Drop the flags (Eric)
Handle in_fence_fd already in job_submit (Eric) Drop extra vc4_fence_context_init (Eric) Dup fds with CLOEXEC (Eric) Mention exact extension name (Eric)
Signed-off-by: Stefan Schake <email@example.com>
Reviewed-by: Eric Anholt <firstname.lastname@example.org>