Follow up r35314. Fix compiler warning.
Follow up r35314. Fix compiler warning.

* subversion/libsvn_subr/prompt.c
  (): Include svn_cmdline_private header in order to fix compiler warning
   of missing prototype.

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