Fix SMP connection status sent from L2CAP when LE ACL is not connected

If L2CAP is already trying to establish the LE ACL and SMP pairing attempt requests for LE connection, SMP layer is immediately informed by L2CAP that it is connected. As a result SMP Pairing request could be sent to L2CAP before the actual connection.
In such a case the SMP packet would be dropped by the L2CAP and pairing will eventually timeout even if the LE ACL is successfully established a little later. This can happen if LE L2CAP socket connection is requested before LE pairing.

This change sends connected status from L2CAP to SMP layer only when the LE ACL has been established.

Test: atest PairingTest
Flag: com.android.bluetooth.flags.smp_connection_status_handling_when_no_acl
Bug: 401053315
Bug: 401073843
Change-Id: Ief654f8286c039404218a802bfff860090ec87e8