Bluetooth: Fix issue with ADV_IND reports and auto-connection handling

Bluetooth: Fix issue with ADV_IND reports and auto-connection handling

When adding remote devices to the kernel using the Add Device management
command, these devices are explicitly allowed to connect. This kind of
incoming connections are possible even when the controller itself is
not connectable.

For BR/EDR this distinction is pretty simple since there is only one
type of incoming connections. With LE this is not that simple anymore
since there are ADV_IND and ADV_DIRECT_IND advertising events.

The ADV_DIRECT_IND advertising events are send for incoming (slave
initiated) connections only. And this is the only thing the kernel
should allow when adding devices using action 0x01. This meaning
of incoming connections is coming from BR/EDR and needs to be
mapped to LE the same way.

Supporting the auto-connection of devices using ADV_IND advertising
events is an important feature as well. However it does not map to
incoming connections. So introduce a new action 0x02 that allows
the kernel to connect to devices using ADV_DIRECT_IND and in addition
ADV_IND advertising reports.

This difference is represented by the new HCI_AUTO_CONN_DIRECT value
for only connecting to ADV_DIRECT_IND. For connection to ADV_IND and
ADV_DIRECT_IND the old value HCI_AUTO_CONN_ALWAYS is used.

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