Remove $FreeBSD$: one-line sh pattern

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

pkgbase: Add a FreeBSD-bluetooth package

Move the bluetooth related files from FreeBSD-runtime to a new package named
FreeBSD-bluetooth
The FreeBSD runtime is only intended to have everything for a working
FreeBSD installation and bluetooth isn't needed for that.

Reviewed by: bapt, gjb
Differential Revision: https://reviews.freebsd.org/D20959

[ath3k] add a replacement ath3k firmware loading tool.

This is influenced by the ath3k driver from linux (circa 2013, this is
how long I've been sitting on this.)

It handles loading in firmware using the newer model, where it assembles
the right set of firmware blobs and board configuration based on the
device list and querying the device.

The older utility could only load in a single image - which sometimes
was ath3k-1.fw and sometimes was ath3k-2.fw. However, the ath3k maintainers
didn't want to keep adding in binaries that were just derivatives with a
separate board config, so they deleted ath3k-2.fw from the Linux firmware
repository and instead, well, did this.

Now, this has been tested against AR3011 and AR3012 NICs from the AR9285+BT
combo up through to the QCA9565+BT combo. It doesn't yet work with the
QCAFN222 NIC as that is some newer chip.

The firmware can be grabbed from https://github.com/erikarn/ath3kfw/ in
the share/firmware/ath3k directory. I'll update this utility over time
to support the newer firmware drops (newer than mid-2013) which should
pull in the QCNFA222 and subsequent chips.

Tested:

* AR9285 + BT
* AR9287 + BT
* AR9485 + BT
* AR9462 + BT
* QCA9565 + BT

Convert usr.sbin to LIBADD
Reduce overlinking

Remove redundant assignments to WARNS.

For these directories, WARNS is already implied to be 6.

Add firmware downloader for Atheros AR3011 based USB Bluetooth devices.

Hardware donated by: Rusty Nejdl rnejdl at ringofsaturn dot com
Tested by: Rusty Nejdl rnejdl at ringofsaturn dot com
Tested by: Andrzej Tobola ato at iem dot pw dot edu dot pl
MFC after: 3 weeks