Name
drm_dp_mst_topology_mgr_resume — 
     resume the MST manager
 
Synopsis
| int drm_dp_mst_topology_mgr_resume ( | struct drm_dp_mst_topology_mgr * mgr ); | 
 
Description
   This will fetch DPCD and see if the device is still there,
   if it is, it will rewrite the MSTM control bits, and return.
   
   if the device fails this returns -1, and the driver should do
   a full MST reprobe, in case we were undocked.