net/hns3: fix flow control mode

net/hns3: fix flow control mode

Currently, hns3 driver doesn't support to flow control auto-negotiation.
The FC mode requested by user is the same as the current FC mode. It is
not necessary to maintain the current FC mode. We only report the current
FC mode based on actual flow control mode in hns3_flow_ctrl_get().

This patch removes this redundant field. In addition, "requested_mode" in
hns3_hw struct indicates the FC mode requested by user, and the name is
unreasonable. It needs to be modified to "requested_fc_mode".

Fixes: 62e3ccc2b94c ("net/hns3: support flow control")
Cc: stable@dpdk.org
Signed-off-by: Huisong Li <lihuisong@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>