drm/i915/gen9: Always apply WaForceContextSaveRestoreNonCoherent

The revision id range for this workaround has changed. So apply
it to all revids on all gen9.

References: HSD#2134449
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465309159-30531-6-git-send-email-mika.kuoppala@intel.com