kconfig: remove unneeded code in expr_compare_type()

The condition (t2 == 0) never becomes true because the zero value
(i.e., E_NONE) is only used as a dummy type for prevtoken. It can
be passed to t1, but not to t2.

The caller of this function only checks expr_compare_type() > 0.
Therefore, the distinction between 0 and -1 is unnecessary.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

scripts/kconfig/expr.c

@@ -1096,11 +1096,8 @@ static int expr_compare_type(enum expr_type t1, enum expr_type t2)
 	case E_OR:
 		if (t2 == E_LIST)
 			return 1;
-	case E_LIST:
-		if (t2 == 0)
-			return 1;
 	default:
-		return -1;
+		break;
 	}
 	return 0;
 }