Bluetooth: host: Fix host resolving peer identity in connection complete

Fix host resolving the peer identity address in enhanced connection
complete event when the resolving list in the controller is full and
resolution is done in the host.
Move the handling from legacy connection complete into enhanced
connection complete event so that it is done for both connection
complete events.

Signed-off-by: Joakim Andersson <joakim.andersson@nordicsemi.no>