Bluetooth: Fix check for direct advertising

These days we allow simultaneous LE scanning and advertising. Checking
for whether advertising is enabled or not is therefore not a reliable
way to determine whether directed advertising was used to trigger the
connection creation. The appropriate place to check (instead of the hdev
context) is the connection role that's stored in the hci_conn. This
patch fixes such a check in le_conn_timeout() which could otherwise lead
to incorrect HCI commands being sent.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.16.x