bnxt_en: Ring free response from close path should use completion ring

bnxt_en: Ring free response from close path should use completion ring

Orabug: 23221795

Use completion ring for ring free response from firmware.  The response
will be the last entry in the ring and we can free the ring after getting
the response.  This will guarantee no spurious DMA to freed memory.

Signed-off-by: Prashant Sreedharan <prashant@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 74608fc98d2856fa7201a498b61c9dd9455b504a)
Signed-off-by: Brian Maly <brian.maly@oracle.com>