Bluetooth: Fix updating SMP remote key distribution information

When performing pairing using SMP the remote may clear any key
distribution bits it wants in its pairing response. We must therefore
update our local variable accordingly, otherwise we might get stuck
waiting for keys that will never come.

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