tcc: fix selfcompilation with tcc. Temporarily disable crashing interface test

vlib/builtin/string.v

@@ -43,10 +43,10 @@ NB: A V string should be/is immutable from the point of view of
 
 
 pub struct string {
-	is_lit bool
 pub:
 	str byteptr // points to a C style 0 terminated string of bytes.
 	len int // the length of the .str field, excluding the ending 0 byte. It is always equal to strlen(.str).
+	is_lit bool
 }
 	// mut:
 	// hash_cache int