NetBSD/OpenBSD/FreeBSD build support

[GitHub pull_request - opened]

alsa-project/alsa-lib pull request #250 was opened from jg1uaa:

to build alsa-lib on *BSD, small fix is required.
(reference: FreeBSD/NetBSD ports diff)

There is no problem to compile modified code on Linux(Debian-11), FreeBSD-13.1, NetBSD-current and OpenBSD-7.1.

Request URL   : https://github.com/alsa-project/alsa-lib/pull/250
Patch URL     : https://github.com/alsa-project/alsa-lib/pull/250.patch
Repository URL: https://github.com/alsa-project/alsa-lib