Update runtime files

runtime/doc/motion.txt

@@ -612,7 +612,8 @@ i)							*v_i)* *i)* *i(*
 i(							*vib* *v_ib* *v_i(* *ib*
 ib			"inner block", select [count] blocks, from "[count] [("
 			to the matching ')', excluding the '(' and ')' (see
-			|[(|).
+			|[(|).  If the cursor is not inside a () block, then
+			find the next "(".
 			When used in Visual mode it is made characterwise.
 
 a>						*v_a>* *v_a<* *a>* *a<*