[ofw] patch: [ibbus] Add A new function to IBAL that allows one to create a multicast group without attaching a QP to it.

[Hefty, Sean]

> On some occasions one might have to create a multicast group but does not
> want to attach a QP to it.
> 
> Any comments (including to function names) are welcomed.

Can you explain such an occasion where a node wants to join a multicast group, but never use it?