Fix an error in the 'svnauth list' help text.

* subversion/svnauth/svnauth.c
  (cmd_table): Document the actual behaviour with multiple patterns.
   The text was saying that credentials were shown if they matched any
   of the provided patterns while, in fact, all patterns must match.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1521492 13f79535-47bb-0310-9956-ffa450edef68