wasm_name_new_from_string should not have +1 since rust strings are not null terminated.

```
wasm_name_t nameWrong;
wasm_name_new_from_string(&nameWrong, "hello");
wasm_name_t nameRight;
wasm_name_new(&nameRight, strlen("hello"), "hello");
```
first one didnt work when adding to the linker.
second one did. 
Issue was caused by `wasm_name_new_from_string` adding to the length.
