cephadm: support for specifying IP a port will be bound to on

cephadm: support for specifying IP a port will be bound to on

This is mostly for checking for port conflicts.
Currently, we just check if the port is bound to
on any IP on the host. This mechanism should allow
certain daemon types to specify a port -> IP mapping
that will be passed to the cephadm binary. That
mapping will then be used by cephadm to only
check for the port being bound to on that specific
IP rather than any IP on the host. The end result
is we could have daemons bound to the same
port on different IPs on the same node.

It's expected that daemon types will set this
up as part of their prepare_create or generate_config
functions where they may have more info about the
specific IPs and ports they need.

Signed-off-by: Adam King <adking@redhat.com>