Bluetooth: Fix accepting connections when not using mgmt

When connectable mode is enabled (page scan on) through some non-mgmt
method the HCI_CONNECTABLE flag will not be set. For backwards
compatibility with user space versions not using mgmt we should not
require HCI_CONNECTABLE to be set if HCI_MGMT is not set.

Reported-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.17+