[Differential] D26757: Fix to join AllHost mcast group again when adding an existing IP address

[gnn (George Neville-Neil)]

gnn accepted this revision.

REPOSITORY
  rS FreeBSD src repository

CHANGES SINCE LAST ACTION
  https://reviews.freebsd.org/D26757/new/

REVISION DETAIL
  https://reviews.freebsd.org/D26757

EMAIL PREFERENCES
  https://reviews.freebsd.org/settings/panel/emailpreferences/

To: yannis.planus_alstomgroup.com, #network, mw, ae, gnn
Cc: ae, imp, freebsd-net-list, melifaro, rscheff