Add some statistic routine to collect the time when vGPU is
scheduled in/out and the time of the last ctx submission.
Signed-off-by: NPing Gao <ping.a.gao@intel.com>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Signed-off-by: NZhenyu Wang <zhenyuw@linux.intel.com>