python/machine: remove unused sock_dir argument

python/machine: remove unused sock_dir argument

By using a socketpair for all of the sockets managed by the VM class and
its extensions, we don't need the sock_dir argument anymore, so remove
it.

We only added this argument so that we could specify a second, shorter
temporary directory for cases where the temp/log dirs were "too long" as
a socket name on macOS. We don't need it for this class now. In one
case, avocado testing takes over responsibility for creating an
appropriate sockdir.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20230928044943.849073-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>