rdate: make it do something remotely sane, facing 32-bit time overflow

function                                             old     new   delta
rdate_main                                           251     254      +3
packed_usage                                       31029   31023      -6

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/inetd.c b/networking/inetd.c
index 4d0ab2e..612284e 100644
--- a/networking/inetd.c
+++ b/networking/inetd.c
@@ -1677,7 +1677,7 @@
 	struct timeval tv;
 
 	gettimeofday(&tv, NULL);
-	return htonl((uint32_t)(tv.tv_sec + 2208988800));
+	return htonl((uint32_t)(tv.tv_sec + 2208988800U));
 }
 /* ARGSUSED */
 static void FAST_FUNC machtime_stream(int s, servtab_t *sep UNUSED_PARAM)