Pull up following revision(s) (requested by plunky in ticket #769):
	sys/dev/bluetooth/bthidev.c: revision 1.23
	sys/dev/bluetooth/bthidev.c: revision 1.24
	usr.sbin/btdevctl/btdevctl.8: revision 1.8
	sys/dev/bluetooth/btmagic.c: revision 1.4
	sys/dev/bluetooth/btmagic.c: revision 1.5
when no link-mode is specified, explicitly set a mode of (int)0
otherwise l2cap_setmode() will fail during connection setup
for bthidev.c, this fixes a problem with Microsoft Wedge Touch
mouse (which may not be able to authenticate)
for btmagic.c, include this fix in case somebody tries that
related to PR/47286
increase some diagnostics
add a comment pointing out that the link-mode may need to be
changed manually, for devices which cannot authenticate
for PR/47286
Ticket 769.