RDMA/bnxt_re: Use separate response buffer for stat_ctx_free

Use separate buffers for the request and response data. Eventhough the
response data is not used, providing the correct length is appropriate.

Link: https://lore.kernel.org/r/1631709163-2287-4-git-send-email-selvin.xavier@broadcom.com


Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>