setup-ssh: only read the ssh port once

Then reuse it. With certain setups, this could be slow when pre-seeding
an entire cluster.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: René Nussbaumer <rn@google.com>

tools/setup-ssh

@@ -220,6 +220,7 @@ def main():
   SetupLogging(options)
 
   passwd = getpass.getpass(prompt="%s password:" % constants.GANETI_RUNAS)
+  ssh_port = netutils.GetDaemonPort("ssh")
 
   # Below, we need to join() the transport objects, as otherwise the
   # following happens:
@@ -231,7 +232,7 @@ def main():
   #   now
 
   for host in args:
-    transport = paramiko.Transport((host, netutils.GetDaemonPort("ssh")))
+    transport = paramiko.Transport((host, ssh_port))
     try:
       transport.connect(username=constants.GANETI_RUNAS, password=passwd)
     except Exception, err: