We use timeout mode, and we need to lower the timeout to get good RC6
residency when loads are running.  This gets me from 0% residency during
glxgears to 77%, which is a pretty good improvement.  This value also
matches the current BWG recommentations.
Tested-by: N"Meng, Mengmeng" <mengmeng.meng@intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NDeepak S <deepak.s@inel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>