wmemcpy_s ESLEMAX check does not multiply dmax by sizeof(wchar_t)

```
    if (dmax > RSIZE_MAX_MEM) {
        invoke_safe_mem_constraint_handler("wmemcpy_s: dmax exceeds max",
                   NULL, ESLEMAX);
        return RCNEGATE(ESLEMAX);
    }
```
Should be 
```
    if (dmax*sizeof(wchar_t) > RSIZE_MAX_STR) {
```