RDMA/rtrs: Cleanup the code in rtrs_srv_rdma_cm_handler

Let these cases share the same path since all of them need to close
session.

Link: https://lore.kernel.org/r/20210325153308.1214057-11-gi-oh.kim@ionos.comSigned-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/ulp/rtrs/rtrs-srv.c

@@ -1908,13 +1908,10 @@ static int rtrs_srv_rdma_cm_handler(struct rdma_cm_id *cm_id,
 	case RDMA_CM_EVENT_UNREACHABLE:
 		rtrs_err(s, "CM error (CM event: %s, err: %d)\n",
 			  rdma_event_msg(ev->event), ev->status);
-		close_sess(sess);
-		break;
+		fallthrough;
 	case RDMA_CM_EVENT_DISCONNECTED:
 	case RDMA_CM_EVENT_ADDR_CHANGE:
 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
-		close_sess(sess);
-		break;
 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
 		close_sess(sess);
 		break;