gvt-fixes-2017-05-11

- vGPU scheduler performance regression fix (Ping)
- bypass in-context mmio restore (Chuanxiao)
- one typo fix (Colin)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170511054736.swpcmnzdoqi75cnl@zhen-hp.sh.intel.com