RDMA/bnxt_re: Fix IB_SEND_IP_CSUM handling in post_send

RDMA/bnxt_re: Fix IB_SEND_IP_CSUM handling in post_send

[ Upstream commit f01765a2361323e78e3d91b1cb1d5527a83c5cf7 ]

The bnxt_re SEND path checks wr->send_flags to enable features such as
IP checksum offload. However, send_flags is a bitmask and may contain
multiple flags (e.g. IB_SEND_SIGNALED | IB_SEND_IP_CSUM), while the
existing code uses a switch() statement that only matches when
send_flags is exactly IB_SEND_IP_CSUM.

As a result, checksum offload is not enabled when additional SEND
flags are present.

Replace the switch() with a bitmask test:

    if (wr->send_flags & IB_SEND_IP_CSUM)

This ensures IP checksum offload is enabled correctly when multiple
SEND flags are used.

Fixes: 1ac5a4047975 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Link: https://patch.msgid.link/20251219093308.2415620-1-alok.a.tiwari@oracle.com
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>