Bluetooth: BAP: BA: Fix sonarcloud issue with assignment and ++

Sonarcloud does not allow to use the result of a incremental
(++) as an assignment.

Signed-off-by: Emil Gydesen <emil.gydesen@nordicsemi.no>

Author: Thalley

subsys/bluetooth/audio/bap_broadcast_assistant.c

@@ -706,13 +706,14 @@ static uint8_t char_discover_func(struct bt_conn *conn,
 		} else if (bt_uuid_cmp(chrc->uuid, BT_UUID_BASS_RECV_STATE) == 0) {
 			if (inst->recv_state_cnt <
 				CONFIG_BT_BAP_BROADCAST_ASSISTANT_RECV_STATE_COUNT) {
-				uint8_t idx = inst->recv_state_cnt++;
+				const uint8_t idx = inst->recv_state_cnt;
 
 				LOG_DBG("Receive State %u", inst->recv_state_cnt);
 				inst->recv_state_handles[idx] =
 					attr->handle + 1;
 				sub_params = &inst->recv_state_sub_params[idx];
 				sub_params->disc_params = &inst->recv_state_disc_params[idx];
+				inst->recv_state_cnt++;
 			}
 		} else {
 			LOG_DBG("Invalid UUID %s", bt_uuid_str(chrc->uuid));