comctl32/listview: fix icon spacing calculation [try 2]

[Nikolay Sivov]

On 1/15/2013 01:53, Daniel Jelinski wrote:
> 2013/1/14 Nikolay Sivov <bunglehead at gmail.com>:
>> This message actually is supposed to be used with MAKELONG(), so it's not
>> truncated in such way.
> Probably (MSDN doesn't say a word about the preferred macro for this
> function, unless you count user comments), however if any app actually
> calls MAKELPARAM, at least it will get the same result as on Windows.
>
It's a way it's used in ListView_SetIconSpacing() (which could be broken 
in its own way of course).
I think it's ok to ignore this 64 bit case for now, especially while we 
don't get daily test runs.