pimd: remove pim and igmp OIFs when ifchannel_delete happens

pimd: remove pim and igmp OIFs when ifchannel_delete happens

In a pim-evpn setup (say TORC11<=>TORC12) an mroute can have a mix of
PIM and IGMP joins. The vxlan termination device ipmr-lo is IGMP
joined on termination mroutes and the peerlink-rif can be pim joined
on the same mroute if the MLAG peer (TORC11) loses all its uplinks to
underlay -
root@TORC12:~# net show pim state 239.1.1.101|grep pimreg
1         *                239.1.1.101      uplink-1
             pimreg(I    ), ipmr-lo( J   ), peerlink-3.4094( J   )
root@TORC12:~#

When the uplinks come back up on TORC11 it will prune the peerlink-rif
and join the RP (say spine) via the uplinks.

TORC12 is rxing the prune and removing the if_channel
(pim_ifchannel_delete). However it is not removing the OIF from
mfcc_ttl basically leaving behind a leaked OIF in the forwarding
entry. And this is because it is deriving the owner flag from the
parent upstream entry and incorrectly concluding that all OIFs are
IGMP joined.

Thix fix flushes out both PIM and IGMP ownership when the ifchannel is
deleted.

There is a second fix in the commit and that is to set the proto mask
correctly (to STAR) for inherited OIFs. (S,G) entries can inherit the
OIF from the (*, G) entry and this decision can change when the pim/igmp
ifchannel is removed. The earlier code was setting the proto-mask
incorrectly to PIM or IGMP.

Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
(cherry picked from commit d4d1d968dbbe61347393f7dace8b675496ff1024)