waitid: always print 5th argument

* wait.c (SYS_FUNC(waitid)): Do not check for tcp->s_ent->nargs
as waitid syscall has 5 arguments.
diff --git a/wait.c b/wait.c
index 156292f..39badf2 100644
--- a/wait.c
+++ b/wait.c
@@ -187,11 +187,9 @@
 		/* options */
 		tprints(", ");
 		printflags(wait4_options, tcp->u_arg[3], "W???");
-		if (tcp->s_ent->nargs > 4) {
-			/* usage */
-			tprints(", ");
-			printrusage(tcp, tcp->u_arg[4]);
-		}
+		/* usage */
+		tprints(", ");
+		printrusage(tcp, tcp->u_arg[4]);
 	}
 	return 0;
 }