_OPSYS_HAS_OSSAUDIO

[nia <nia%NetBSD.org@localhost>]

Hi all,

This variable is defined in every single mk/platform file, having been
copy and pasted between them. It's defined rather inconsitently, it says
it's for "libossaudio" (which is a NetBSD-ism), however, FreeBSD also
defines it to "yes".

Other operating systems that include some kind of implementation of the
Open Sound System (including Solaris, OpenBSD, UnixWare, DragonFly, and
Linux) define it to "no".

As a result, anything relying on this variable is buggy.

Currently only one package uses this variable. I'd like to change it
to use OSS_TYPE instead and then remove the variable definition from
the mk/platform files.