Removed ifdef for <sys/sockio.h> vs <sys/ioctl.h>. <sys/sockio.h> is
a BSD4.4Lite1 feature, not a FreeBSD feature. <sys/ioctl.h> is a
compatibility misfeature.

Moved NPCI ifdef. This file didn't compile if NPCI <= 0. It shouldn't
be configured in that case, but it is easy to support (mis)configuration
of drivers without buses by generating null objects, and many drivers
do it.

Removed unused includes.