pimd: OIF add with PROTO_PIM is not happening if join rxed in PP state

pimd: OIF add with PROTO_PIM is not happening if join rxed in PP state

Dumps while in problem state -
============================
[from "show ip pim state"]
Active Source           Group            RPT  IIF               OIL
1      6.0.0.31         239.1.1.111      n    swp1              swp4( J * )
[from "show ip pim join"]
Interface        Address         Source          Group           State      Uptime   Expire Prune
swp3             6.0.0.22        6.0.0.31        239.1.1.111     JOIN       --:--:-- 03:11  --:--

You can see from the dumps that the pim downstream router has joined on
swp3 but that OIF has not been added to the OIL with flag
PIM_OIF_FLAG_PROTO_PIM. This is because the join was rxed while the
ifchannel was in a prune-pending state.

Relevant logs -
===============
[
PIM: recv_prune: prune (S,G)=(6.0.0.31,239.1.1.111) rpt=1 wc=0 upstream=6.0.0.22 holdtime=210 from 6.0.0.28 on swp3
PIM: pim_upstream_ref(pim_ifchannel_add): upstream (6.0.0.31,239.1.1.111) ref count 3 increment
PIM: pim_upstream_add(pim_ifchannel_add): (6.0.0.31,239.1.1.111), iif 6.0.0.26/0 (swp1) found: 1: ref_count: 3
PIM: pim_ifchannel_add: ifchannel (6.0.0.31,239.1.1.111) is created
PIM: pim_joinprune_recv: SGRpt flag is set, del inherit oif from up (6.0.0.31,239.1.1.111)
PIM: pim_mroute_add(pim_channel_del_oif), vrf default Added Route: (6.0.0.31,239.1.1.111) IIF: swp1, OIFS: swp4
PIM: pim_channel_del_oif(pim_joinprune_recv): (S,G)=(6.0.0.31,239.1.1.111): proto_mask=4 IIF:1 OIF=swp3 vif_index=3
PIM: recv_join: join (S,G)=(6.0.0.31,239.1.1.111) rpt=0 wc=0 upstream=6.0.0.22 holdtime=210 from 6.0.0.28 on swp3
PIM: PIM_IFCHANNEL(swp3): (6.0.0.31,239.1.1.111) is switching from SGRpt(PP) to JOIN
PIM: Sending Request for New Channel Oil Information(6.0.0.31,239.1.1.111) VIIF 1(default)
]

Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>