Follow-up to r23575.
Follow-up to r23575.

* subversion/include/svn_error_codes.h
  (SVN_ERR_RA_SVN_NO_MECHANISMS): Add '@since' docstring.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion