net/bnxt: limit Rx representor packets per poll

net/bnxt: limit Rx representor packets per poll

Without some limit on the number of packets transferred from the
HW ring to the representor ring per burst receive call, an entire ring's
worth of packets can be transferred. This can break assumptions
about ring indices (index on return could be identical to the index
on entry, which is assumed to mean that no packets were processed),
and can result in representor packets being dropped unnecessarily
due to representor ring overflow.

Fix by limiting the number of representor packets transferred per
poll to requested burst size.

Fixes: 6dc83230b43b ("net/bnxt: support port representor data path")
Cc: stable@dpdk.org
Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>