Removed useless comparisons

Unsigned values are always non-negative which caused comparisons
using this to create warnings on RHEL5.

server/modules/routing/binlog/blr_master.c

@@ -1334,7 +1334,7 @@ blr_handle_binlog_record(ROUTER_INSTANCE *router, GWBUF *pkt)
                 int event_limit = router->mariadb10_compat ?
                                   MAX_EVENT_TYPE_MARIADB10 : MAX_EVENT_TYPE;
 
-                if (hdr.event_type >= 0 && hdr.event_type <= event_limit)
+                if (hdr.event_type <= event_limit)
                 {
                     router->stats.events[hdr.event_type]++;
                 }