Fix bad conn_id being closed

Fix: pass the right conn_id to close.
When multiple service discoveries are scheduled, we can't guarantee that
conn_id is still pointing to the connection we want to close one second
after the discovery was finished. It might point to the next service
discovery in progress.

Flag: com::android::bluetooth::flag::bta_dm_disc_close_proper_conn_id
Bug: 399687217
Bug: 398724895
Test: manual, bond with sony inzone buds
Change-Id: I370307f51b64eed390e2f90dabb5457b4c5096a0