The math/asir2000 port includes the <sgtty.h> header file on FreeBSD,
even though it isn't needed (one might wonder which platform *does* need
it). We'd better not include it, because sgtty.h has been deprecated for
a very very long time.

PR: 119106
Submitted by: Ed Schouten <ed@fxq.nl>
Approved by: maintainer