Bluetooth: Don't bother user space without IO capabilities

If user space has a NoInputNoOutput IO capability it makes no sense to
bother it with confirmation requests. This patch updates both SSP and
SMP to check for the local IO capability before sending a user
confirmation request to user space.

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