net/hns3: fix return value when clearing statistics

net/hns3: fix return value when clearing statistics

Since the return value of the '.stats_reset' and '.xstats_reset'
callback function is int, when failing to issue command to firmware to
execute clear statistics, the relevant callback function should return
non-zero value.

Fixes: 8839c5e202f3 ("net/hns3: support device stats")
Cc: stable@dpdk.org
Signed-off-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>