Use vgpu_pm functions for vgpu instead of gk20a_pm functions in suspend and resume. Change-Id: I9d23cd612caa3e6fa9be65d60ccdba3b7f893350 Signed-off-by: Jinyoung Park <jinyoungp@nvidia.com> Reviewed-on: https://git-master.nvidia.com/r/1544161 Reviewed-by: Thomas Fleury <tfleury@nvidia.com> Tested-by: Thomas Fleury <tfleury@nvidia.com> Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com> Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com> Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com> GVS: Gerrit_Virtual_Submit