RDMA/bnxt_re: Fix Send Work Entry state check while polling completions

Some adapters need a fence Work Entry to handle retransmission.  Currently
the driver checks for this condition, only if the Send queue entry is
signalled. Implement the condition check, irrespective of the signalled
state of the Work queue entries

Failure to add the fence can result in access to memory that is already
marked as completed, triggering data corruption, transmission failure,
IOMMU failures, etc.

Fixes: 9152e0b7 ("RDMA/bnxt_re: HW workarounds for handling specific conditions")
Link: https://lore.kernel.org/r/1574671174-5064-3-git-send-email-selvin.xavier@broadcom.com


Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>