[PATCH] Detect GNU/kFreeBSD in user-visible kernel headers (v2)

Here we go again :-)

Out of the kernel headers that are installed in /usr/include/ hierracy, there
are some which include support multiple operating systems (usually FreeBSD and
other *BSD flavours).

This patch adds support to detect GNU/kFreeBSD as well.  In all cases, we
match the same declarations as FreeBSD does (which is to be expected in kernel
headers, since both systems share the same kernel).

-- 
Robert Millan