drm/i915/gvt: update misc ctl regs base on stepping info

Misc ctl related registers are for WA purpose, should detect the
stepping info first before updating HW value.

Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
1 file changed