removing SVR4 binary compatibilty layer

[Gleb Smirnoff]

On Wed, Feb 15, 2017 at 10:56:29AM +0330, mokhi wrote:
m> Is this removing is because no-interest on maintaining it?
m> 
m> If it helps, I am working to use the `kern_* instead sys_*` as
m> mentioned patch in that discussion suggests for svr4, if this helps.

Well, we all "maintain" it, meaning that we keep it compilable. However,
I'm sure that no one checks the functionality. There are no regression
tests, and seems to be no users. I recently found that if you run
GENERIC and 'kldload svr4.ko', the socket layer compatibility will
be broken, since SVR4 requires COMPAT_OLDSOCK. And that has been for
decades, and no one notices that. I bet there are simply no users.

Towing this piece of code into the future is just a waste of time.

-- 
Totus tuus, Glebius.