Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

bthidd(8): Add evdev protocol support for bluetooth keyboards and mouses

User-visible changes:

"-u" is added to to list of command line options supported by bthidd.
Use it to enable evdev support. uinput and evdev modules should be
kld-loaded or compiled into the kernel in that case.

bthidd_evdev_support rc.conf variable is added to control enabling of
evdev support in bthidd startup script. Possible values are: "YES", "NO",
"AUTO"(default). Setting bthidd_evdev_support to "AUTO" inserts "-u" option
if kernel is compiled with EVDEV_SUPPORT option enabled.

Support for consumer HID usage page keyboard events is implemented. Most of
them are available only through evdev protocol.

kern.evdev.rcpt_mask sysctl is checked, so "sysctl kern.evdev.rcpt_mask=12"
should be executed if EVDEV_SUPPORT is compiled into kernel.

It is recommended to regenerate bthidd.conf entries with bthidcontrol(8)
"Query" command to set user-friendly names of bluetooth devices.

Reviewed by: emax, gonzo, wblock (docs), bcr (docs, early version)
Differential Revision: https://reviews.freebsd.org/D13456