ws2_32: Only examine lower-order bits in getsockopt/setsockopt

[Juan Lang]

Hi Detlef,

> When reading the log in the bug, the WSAAsyncGetHostByName16 is the
> indicator for an 16bit app.

Right you are.  I ignored that, but clearly I was mistaken.

> Attached is my diff from last year for that code.

The changes you made to getsockopt16 and setsockopt16 look correct.
The tests you added only trace values, whereas Jeff showed that my
patch is in fact wrong.

So:  it seems as though your changes to getsockopt16 and setsockopt16,
and Jeff's tests, should get sent in.  Do you want to send them in, or
would you prefer that I do?

Thanks,
--Juan