ITS#8563 - Fix missing mentions of back-mdb

doc/guide/admin/replication.sdf

@@ -225,7 +225,7 @@ in the replication context.
 
 The syncrepl engine, which is a consumer-side replication engine,
 can work with any backends. The LDAP Sync provider can be configured
-as an overlay on any backend, but works best with the {{back-bdb}}
+as an overlay on any backend, but works best with the {{back-bdb}},
 {{back-hdb}}, or {{back-mdb}} backends.
 
 The LDAP Sync provider maintains a {{EX:contextCSN}} for each

doc/guide/admin/slapdconf2.sdf

@@ -683,8 +683,8 @@ conforms to the obsolete {{changelog}} format. If the {{EX:syncdata}}
 parameter is omitted or set to {{EX:"default"}} then the log
 parameters are ignored.
 
-The {{syncrepl}} replication mechanism is supported by the {{bdb}} and
-{{hdb}} backends.
+The {{syncrepl}} replication mechanism is supported by the {{bdb}},
+{{hdb}}, and {{mdb}} backends.
 
 See the {{SECT:LDAP Sync Replication}} chapter of this guide for
 more information on how to use this directive.