Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r251129: libpcap 1.4.0.

MFC r241231:

MFV: libpcap 1.3.0.

MFC: libpcap 1.2.1.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Merge libpcap-1.1.1.

Revert previous commit that commented out some bpf functions.
Unconstify arguments of bpf_image(), bpf_filter() and bpf_dump(). This
is needed because some ports rely heavely on these arguments (some of
them even roll out their own implemenentations of bpf_dump).

Merge libpcap 1.0.0.

Import of libpcap 1.0.0.