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

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

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

Approved by: re (implicit)

Add inet_ntoa_r, a reentrant version of inet_ntoa. This is
available on a lot of platforms, as well as libkern for years.

Submitted by: "MQ"

Use C comments since we now preprocess these files with CPP.

- Merge our local changes.
- Exclude unnecessary functions for us.