The table lists the C-(S,G) mapped to the Ldp Provider-Network
Multicast Service Interface (PMSI).
An entry in vRtrPimNgLdpPmsiCGrpSrcTable is created whenever a C-(S,G)
is mapped to a PMSI interface. An entry will be deleted automatically
when the mapping between C-(S,G) and Ldp PMSI is removed.