bug#24230: 25.1.50; vc-mode and svn+ssh:// URLs

[Alfred M. Szmidt]

   > When working with SVN repositories and doing C-x v l on a file I get
   > the following:
   > 
   >   Working file: /home/ams/Makefile
   >   svn: E170013: Unable to connect to a repository at URL 
'svn+ssh://carbonium/svn/com/ams/trunk/Makefile'
   >   svn: E210002: To better debug SSH connection problems, remove the -q 
option from 'ssh' in the [tunnels] section of your Subversion configuration 
file.
   >   svn: E210002: Network connection closed unexpectedly
   > 
   > Commiting and other operations fail as well, but only if one uses the
   > svn+ssh:// protocol.
   > 
   > 
   > In GNU Emacs 25.1.50.4 (x86_64-unknown-linux-gnu, GTK+ Version 3.20.6)
   >  of 2016-07-24 built on scandium
   > Repository revision: 098d29af10a869e65a36804579f16edc49aabcfa
   > System Description:        Arch Linux

   I cannot reproduce this with today's master.

   What do you get if you invoke the equivalent command from the shell
   command line?  Do you perhaps get any prompts, e.g. for pass phrase or
   something?

Yeah, I get a password prompt; I can mitigate the issue by using
public keys.  Do you want the output from ssh/svn?