Make the SRIOV-Capable device invisible from SOS if there is
no room for its all virtual functions.
v2: fix a issue that if a PF has been dropped, the subsequent PF
will be dropped too even there is room for its VFs.
Tracked-On: #4433
Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>