oledb32: Fix a memory leak (Coverity).

dlls/oledb32/datainit.c

@@ -577,6 +577,7 @@ static HRESULT get_dbpropset_from_proplist(struct dbprops *props, DBPROPSET **pr
         if (FAILED(hr))
         {
             ERR("failed to init property %s value as type %d\n", debugstr_w(pair->name), descr->type);
+            SysFreeString(provider_string);
             free_dbpropset(1, *propset);
             *propset = NULL;
             return hr;