sys: Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

sys/modules: normalize .CURDIR-relative paths to SRCTOP

This simplifies make output/logic

Tested with: `cd sys/modules; make ALL_MODULES=` on amd64
MFC after: 1 month
Sponsored by: Dell EMC Isilon

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

- Import the HEAD csup code which is the basis for the cvsmode work.

Back out previous commits. Installing new share/mk fixes this.

NO_MAN is now NOMAN.

Fix kernel modules build. For some reason, this module now bails out with
an error that there is no aicasm.1 man page.

Hook the aic7xxx modules up. This requires some extra care since aicasm
is a compiler tool and needs to be compiled by the host compiler. I've
tested this in i386->sparc cross-build, 4.7->current upgrade, normal
buildkernel target, and normal /sys/i386/compile/GENERIC configurations.

Submitted by: ru

Add cleandepend target.

Pass the cleandir target on to the aicasm Makefile. This should
fix the buildkernel target.

Complete the hookup of ahd/ahc module building.

Allow the ahc and ahd drivers to be built as modules. This also
breaks the ahc driver into a core back-end and pci and eisa
front-ends.