Merge r1688660 from trunk:

mod_authz_dbd: Avoid a crash when lacking correct DB access permissions. PR 57868.

Submitted by: Jose Kahan <jose w3.org>

Submitted by: ylavic
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1701404 13f79535-47bb-0310-9956-ffa450edef68