GNU/kFreeBSD support: fixes in code specific to kernel of FreeBSD

[Robert Millan]

Here are a few fixes for code that is specific to kernel of FreeBSD. Some of the fixes also improve FreeBSD support, some don't.

• alsa.diff: FreeBSD doesn't support ALSA. It supports PULSE though.

• fbsd_version.diff: Descriptor index transition happened specifically n 700044. This makes the check more accurate on FreeBSD. On GNU/kFreeBSD it is needed because __FreeBSD__ macro isn't available (__FreeBSD_version is available only when building kernel modules).

• netif_freebsd.diff: Glibc portability fix (include <stdlib.h> and avoid using private definitions which are FreeBSD-only).

• redundant_check.diff: There's no need to check for RT_OS_FREEBSD in a file that is already FreeBSD-only.

• aio_listio_max.diff: Glibc doesn't provide AIO_LISTIO_MAX. Instead it has to be queried in rntime with sysconf().

• slirp.diff: Building slirp.c on Glibc requires _GNU_SOURCE (otherwise POLLRDNORM is not available)

[Robert Millan]

Btw, all patches I have submitted here are copyright 2011 Robert Millan and I hereby license them under the MIT license (​http://www.virtualbox.org/wiki/MIT%20license)

[Robert Millan]

Any news about this?

[aeichner]

Please use the vbox-dev mailing list for such patch series.