net/hns3: fix statistics

net/hns3: fix statistics

This patch fixes the statistics problems for sending and receiving
message as belows:

1.In receiving direction, for FCS error messages, drivers should not
record them in rte_eth_stats.ipackets statistics.

2.In sending direction, for messages of illegal length, too long or
equals 0, drivers should not notify the network card hardware to
send them, should not continue to send the remaining message in burst,
and record them in rte_eth_stats.opackets statistics.

Fixes: 8839c5e202f3 ("net/hns3: support device stats")

Signed-off-by: Hao Chen <chenhao164@huawei.com>
Signed-off-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>