zsh does not offer ssh host from config

[Jan Palus <jpalus@fastmail.com>]

Hi,

I've got a single real hostname starting with 'build' prefix which is present
in my known_hosts file. I also have a couple Host specifications in ssh config
file having names starting with 'build' but real HostName does not resolve to
name starting with 'build'. When doing `ssh build<tab>` I'd expect to be
offered both real hostname as well as Host specification names, however only
real hostname is immediately completed. That's because of _ssh_hosts returning
on successful hosts completion:

# If users-hosts matches, we shouldn't complete anything else.
if [[ "$IPREFIX" == *@ ]]; then
  _combination -s '[:@]' my-accounts users-hosts "users=${IPREFIX/@}" hosts "$@" && return
else
  _combination -s '[:@]' my-accounts users-hosts \
    ${opt_args[-l]:+"users=${opt_args[-l]:q}"} hosts "$@" && return # <--- HERE
fi

Is this intentional that config file parsing is skipped entirely if host was
completed successfully?