Overlay Controller bugfixes and underlay BFD

[ClausHolbechArista]

Change Summary

Fix underlay BGP session config and add knob to enable bfd on underlay.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Documentation content changes
• Other (please describe):

Related Issue(s)

Component(s) name

eos_l3ls_evpn

Proposed changes

# Enable BFD for p2p BGP sessions - useful if the overlay_controller is a VM | Optional
overlay_controller_p2p_bfd: < true | false | default -> false >

and fix missing remote-as for underlay BGP on Overlay Controllers

How to test

Checklist:

• My code has been rebased from devel before I start
• I have read the CONTRIBUTING document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have updated molecule CI testing accordingly
• All new and existing tests passed (pre-commit, make linting and make sanity-lint).

[onurgashi]

LGTM!

[titom73]

Looks Good to me!