Bluetooth: Add skeleton for SMP self-tests

This patch adds the initial skeleton and kernel config option for SMP
self-tests.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --cc net/bluetooth/Kconfig
Simple merge

diff --cc net/bluetooth/selftest.c
Simple merge

diff --cc net/bluetooth/smp.c
Simple merge

diff --cc net/bluetooth/smp.h
Simple merge