Unhandled identity in bt_conn_create_slave_le

[pdunaj]

Describe the bug
See the following line in bt_conn_create_slave_le:
conn = bt_conn_lookup_addr_le(BT_ID_DEFAULT, peer);

Lookup is done on the default identity whereas connection can be done on some other identity.

To Reproduce
Steps to reproduce the behavior:

1. Create 2 identities.
2. Advertise (directly) on second identity.
3. Connect to peer.
4. Advertise (directly) again on the same identity.
5. See that pending connection is ignored.

Expected behavior
Lookup should do check on the identity passed via parameters to the function.

Impact
Depending on the project. Can be a showstopper.

Screenshots or console output
N/A

Environment (please complete the following information):
ncs zephyr: a288e8b8ab54c667c6ed9776042200411710a9cf (from 06ab394 upstream)

Additional context
N/A