gh-142282 Fix winreg_QueryValueEx_impl to use retSize

retSize was ignored
bufSize is the size of buffer including uninitializd buffers.

Author: youknowone

PC/winreg.c

@@ -1651,7 +1651,7 @@ winreg_QueryValueEx_impl(PyObject *module, HKEY key, const wchar_t *name)
         return PyErr_SetFromWindowsErrWithFunction(rc,
                                                    "RegQueryValueEx");
     }
-    obData = Reg2Py(retBuf, bufSize, typ);
+    obData = Reg2Py(retBuf, retSize, typ);
     PyMem_Free(retBuf);
     if (obData == NULL)
         return NULL;