dlls: add wpcap

[Tomas Carnecky]

James Hawkins wrote:
> +@ stdcall pcap_setbuff(ptr long) wine_pcap_setbuff
> 
> As I said before, you don't need to forward these, just name the APIs
> like they are in the spec file and it should work.
> 

You can see that wine_pcap_close() calls pcap_close() which is a
function implemented in the pcap library (see www.tcpdump.org), so
naming the functions pcap_?? is not possible.

tom