The value of vRtrPimNgGrpSrcRpfSecNbrAddrTyp indicates the type of
the address of the secondary RPF neighbor.
The value of this object is applicable only when the value of the
object vRtrPimNgAFGenMvpnUMHSelection is set to 'tunnelstatus'
indicating that the MVPN is configured with source redundancy.
When MVPN is configured with source redundancy, MVPN is capable of
receiving traffic from two different PE's for the same source.