Flatten sysdeps/unix/bsd/bsd4.4 into sysdeps/unix/bsd

[David Miller]

From: Roland McGrath <roland@hack.frob.com>
Date: Wed,  9 May 2012 12:59:09 -0700 (PDT)

>> I consider it important to make it easier for people to find their way 
>> around the source tree.
> 
> This particular set of changes is quite marginal in that regard.

It's one of many steps to get to an intended destination, in that
regard all such changes are important and anything but marginal.