Without ng_h4 gone, there's no need for hcseriald.

Sponsored by:		Netflix

It was caused by 79a100e28e3c814773bb4c1826cfa25fbe31140e.

- new sentence, new line
- sections out of conventional order: Sh FILES
- unusual Xr order: bthost(1) after bthidd(8)
- no blank before trailing delimiter
- whitespace at end of input line
- sections out of conventional order: Sh EXIT STATUS

MFC after:	1 week

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

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

Sponsored by:	Dell EMC Isilon

Off by default, build behaves normally.
WITH_META_MODE we get auto objdir creation, the ability to
start build from anywhere in the tree.

Still need to add real targets under targets/ to build packages.

Differential Revision:       D2796
Reviewed by: brooks imp

Reduce overlinking