bind-to-interface option

[David Ahern]

Hi:

The openssh suite of commands have an option to specify address (e.g, 
ListenAddress for sshd) but I do not see support for bind-to-interface.

The motivating use case for me is using openssh commands (sshd, ssh, 
scp, sftp) with the recent VRF capability added to the Linux kernel. The 
VRF design relies on the bind-to-interface option to select the correct 
routing tables. Before I started working on patches I wanted to get a 
sense of whether it would be accepted.

Thanks,
David