Merge tag 'gvt-next-2017-12-22' of https://github.com/intel/gvt-linux into drm-intel...

gvt-next-2017-12-22:

- more mmio switch optimization (Weinan)
- cleanup i915_reg_t vs. offset usage (Zhenyu)
- move write protect handler out of mmio handler (Zhenyu)

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171222085141.vgewlvvni37dljdt@zhen-hp.sh.intel.com