net/frr FEATURE add listen range to peer-groups to allow dynamic neighbors

[lonk95]

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Is your feature request related to a problem? Please describe. It is possible to specify an IP range for valid neighbors using FRR. This is particularly useful when you have many neighbors to manage. I'm wondering if we could add a way to configure this from the UI.

Describe the solution you'd like I'm proposing a setup where you link some range of neighbors to a peer-group. This allows you to manage multiple possibly dynamic BGP neighbors. Example config snippet below.

 neighbor MyGroup peer-group
 neighbor MyGroup remote-as xxxxx
 neighbor MyGroup update-source eno1
 bgp listen range x.x.x.x/x peer-group MyGroup

This could be added as a new entry under peer-group: name: bgp listen range summary: An optional IP range that defines valid neighbor IPs for the peer-group