IGMPv3 group record states not handled properly

[troglobit]

Group record states other than IS_EX({})/TO_EX({}) and IS_IN({})/TO_IN({}) are not handled properly in mrouted.

The IGMPv3 support in mrouted is cannot be fully supported, because DVMRP does not have any kind of source tracking, but record states for IS_EX({x})/TO_EX({x}) and IS_IN({x})/TO_IN({x}) should be handled gracefully according to RFC5790. I.e., translated to (*,G) join/leave where appropriate and ignored otherwise.

The pimd igmp_proto.c:accept_membership_report() function has a good example of how this can be handled. Note, it handles sources which mrouted does not. So cases where sources are handled do not apply and need to be translated.