fix -h

doc/man/man8/slapd.8

@@ -117,7 +117,7 @@ The
 .B \-h
 option may be used to specify LDAP (and other scheme) URLs to serve.
 For example, if slapd is given
-.B \-h " ldap://127.0.0.1:9009/ ldaps:/// ldapi:///", 
+.B "\-h \(dqldap://127.0.0.1:9009/ ldaps:/// ldapi:///\(dq", 
 It will bind 127.0.0.1:9009 for LDAP, 0.0.0.0:636 for LDAP over TLS,
 and LDAP over IPC (Unix domain sockets).  Host 0.0.0.0 represents
 INADDR_ANY.