net/bnxt: fix Rx mbuf and agg ring leak in dev stop

net/bnxt: fix Rx mbuf and agg ring leak in dev stop

In the start/stop_op operation, mbufs allocated for rings were not freed

1) add bnxt_free_tx_mbuf/bnxt_free_rx_mbuf in bnxt_dev_stop_op to free MBUF
   before freeing the rings.
2) MBUF allocation and free routines were not in sync. Allocation uses the
   ring->ring_size including any rounded up and multiple factors while the
   free routine uses the requested queue size.

Fixes: c09f57b49c13 ("net/bnxt: add start/stop/link update operations")
Cc: stable@dpdk.org
Signed-off-by: Jay Ding <jay.ding@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Randy Schacher <stuart.schacher@broadcom.com>
Signed-off-by: Xiaoxin Peng <xiaoxin.peng@broadcom.com>
Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>