net/frr: Add remove-private-AS for BGP Neighbors

[rfrederick]

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Is your feature request related to a problem? Please describe. Have an instance where a BGP neighbor needs to be configured to not be sent private ASNs in outbound updates. From what I see the appropriate option is currently not available in the GUI.

Describe the solution you'd like Inclusion of the remove-private-AS option in the GUI for BGP neighbors.

Command overview:

neighbor <A.B.C.D|X:X::X:X|WORD> remove-private-AS [all] [replace-AS] Remove private ASNs in outbound updates

The parameter all applies removal to all AS numbers

The parameter replace-AS replaces private ASNs with our ASN in outbound updates

Describe alternatives you've considered

Additional context

[Monviech]

Should be very simple to add, here is an example

https://github.com/opnsense/plugins/pull/4611/files

Maybe you want to give it a shot? I'll review a PR.

[rfrederick]

I can give it a shot. I'll work up a PR and get it submitted.

[rfrederick]

I've created PR #5090 for this.