On svn-auth-x509 branch, fix comment/formatting.

* subversion/libsvn_subr/x509parse.c
  (x509parse_dn_gets): Fix comment describing the function and 
    wrap the declartion.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/svn-auth-x509@1605845 13f79535-47bb-0310-9956-ffa450edef68