On Solaris, for 64-bit builds, use the 64-bit pcap-config.

On Solaris, for 64-bit builds, use the 64-bit pcap-config.

There are two versions of pcap-config supplied on Solaris (or, at least,
on 64-bit Solaris) - a version that has the right --libs output to find
the 32-bit libraries and a version that has the right --libs output to
find the 64-bit libraries.

Try to figure out whether we're doing a 32-bit or 64-bit build (based on
the pointer size) and, for 64-bit builds, run the 64-bit version of
pcap-config.