Bluetooth: Use lower timeout for LE auto-connections

When we establish connections as a consequence of receiving an
advertising report it makes no sense to wait the normal 20 second LE
connection timeout. This patch modifies the hci_connect_le function to
take an extra timeout value and uses a lower 2 second timeout for the
auto-connection case. This timeout is intentionally chosen to be just a
bit higher than the 1.28 second timeout that High Duty Cycle Advertising
uses.

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