libbluetooth: Move to the bluetooth-lib package

Move the library, but not any of the runtime.  This allows executables
to link against libbluetooth without having to pull in the entire BT
stack.

MFC after:	3 days
Reviewed by:	dch, emaste
Sponsored by:	https://www.patreon.com/bsdivy
Differential Revision:	https://reviews.freebsd.org/D53016

lib/libbluetooth/Makefile

@@ -1,6 +1,8 @@
 # $Id: Makefile,v 1.5 2003/07/22 18:38:04 max Exp $
 
 PACKAGE=	bluetooth
+LIB_PACKAGE=
+
 CONFS=		hosts protocols
 CONFSDIR=	/etc/bluetooth
 CONFSMODE_protocols=	444