st/dri: fix android fence regression

Fixes piglit - egl_khr_fence_sync/android_native tests.
Broken by 884a0b2a9e55d4c1ca39475b50d9af598d7d7280.

Introduce state-tracker flush flags, analogous to the pipe ones. Use
the former when with stapi->flush().

Fixes: 884a0b2a9e5 ("st/dri: use stapi flush instead of pipe flush
when creating fences")
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
3 files changed