Fix CMSG and ALIGN macro usage.
Previously we had to include <machine/param.h> or <sys/param.h> bogusly
due to the fact that <sys/socket.h> CMSG macros needed the ALIGN macro,
which was defined in param.h. However, including param.h was a disaster
for namespace pollution.
This solution, as contributed by shin a while ago, fixes it elegantly
by wrapping the definitions around some namespace pollution preventer
definitions.
This patch was long overdue.
This should allow any network programmer to use <sys/socket.h> as
before.

PR: 19971, 20530
Submitted by: Martin Kaeske <MartinKaeske@lausitz.net>

		Mark Andrews <Mark.Andrews@nominum.com>

Patch submitted by: shin
Reviewed by: bde