Start the implementation of neighbour entry resource limits.
This is split out from D22447.
The reason I am posting this now is that (a) logic can be reviewd and
(b) that we can start talking about a suitable interface for adjusting
the maximum value which is now set on the llatbl and hence harder to
adjust. Ideally we'd want a way to manage it properly as an llatbl
interface (kernel and user space), ettting a default per PF and also
allowing us to change it on a per-interface value.
I'll be open to suggestions as to how to do that (normally arp and ndp
are the tools to manipulate the table ...)