mlang: Forward IMultiLanguage_GetCharsetInfo to IMultiLanguage3_GetCharsetInfo.

dlls/mlang/mlang.c

@@ -2093,8 +2093,8 @@ static HRESULT WINAPI fnIMultiLanguage_GetCharsetInfo(
     BSTR Charset,
     PMIMECSETINFO pCharsetInfo)
 {
-    FIXME("\n");
-    return E_NOTIMPL;
+    ICOM_THIS_MULTI(MLang_impl, vtbl_IMultiLanguage, iface);
+    return IMultiLanguage3_GetCharsetInfo((IMultiLanguage3*)&This->vtbl_IMultiLanguage3, Charset, pCharsetInfo);
 }
 
 static HRESULT WINAPI fnIMultiLanguage_IsConvertible(