Define HAVE_PCAP_LIST_DATALINKS, HAVE_PCAP_FREE_DATALINKS, and

Define HAVE_PCAP_LIST_DATALINKS, HAVE_PCAP_FREE_DATALINKS, and
HAVE_PCAP_SET_DATALINK only if we have the WinPcap development package;
otherwise, don't define them - if you don't have the WinPcap development
package when building on Windows, we don't define HAVE_LIBPCAP, so we
won't include any of the code controlled by those ifdefs in any case,
and, if you do have the WinPcap development package, you'll need to have
the 4.1 version (you won't need WinPcap 4.1 at run time, but you will
need the 4.1 development package at build time).

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@32230 f5534014-38df-0310-8fa8-9805f1628bb7