bnxt_en: Need to include RDMA rings in bnxt_check_rings().

With recent changes to reserve both L2 and RDMA rings, we need to include
the RDMA rings in bnxt_check_rings().  Otherwise we will under-estimate
the rings we need during ethtool -L and may lead to failure.

Fixes: fbcfc8e4 ("bnxt_en: Reserve completion rings and MSIX for bnxt_re RDMA driver.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>