Update cfg option network_for_ssh's help msg

   cfg option network_for_ssh's help msg says "use_floatingip_for_ssh
=true", but now use_floatingip_for_ssh is deprecated, and its value
cannot be "true" or "false" any longer, so it should refer to
connect_method instead.

Change-Id: I4690c8dc1ad0c14ea3e62e54314044e13c688581
Closes-Bug: #1581376
1 file changed