drm_hwcomposer: Set timeouts for fence waits

Instead of waiting forever for fences, set some reasonable timeouts
so we can move on with life if a fence doesn't signal.

BUG=chrome-os-partner:45868
TEST=Tested on smaug with osmos, recovered from fence timeouts

Change-Id: I7f18d684d483d789f228cbad8d5a3e43ac898a43
Signed-off-by: Sean Paul <seanpaul@chromium.org>
3 files changed