Bluetooth: Remove redundant IRK lookup

When processing passive scanning results we need the resolved identity
address both in check_pending_le_conn() as well as later in
process_adv_report(). Since process_adv_report() calls
check_pending_le_conn() we can simply resolve the IRK earlier in the
function and thereby eliminate a second lookup.

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