Remove an erroneous doc string comment that I added in r11869.
Remove an erroneous doc string comment that I added in r11869.

* subversion/include/svn_opt.h
  (svn_opt_parse_revision): Fix doc string.

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