htpasswd/htdbm: Fix hash generation bug. PR 54735

trunk patch: https://svn.apache.org/r1465115

Submitted by: MadMaverick9 <asfbugzilla meinkino.ch>
Reviewed by: sf, covener, minfrin


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1476674 13f79535-47bb-0310-9956-ffa450edef68