sd-bus: drop SD_BUS_CREDS_AUGMENT flag

On checking if the message has enough credentials, the special flag
needs to be dropped.

Fixes a bug introduced by 705a415f68.

src/libsystemd/sd-bus/bus-convenience.c

@@ -655,7 +655,7 @@ _public_ int sd_bus_query_sender_creds(sd_bus_message *call, uint64_t mask, sd_b
         c = sd_bus_message_get_creds(call);
 
         /* All data we need? */
-        if (c && (mask & ~c->mask) == 0) {
+        if (c && (mask & ~SD_BUS_CREDS_AUGMENT & ~c->mask) == 0) {
                 *ret = sd_bus_creds_ref(c);
                 return 0;
         }