net: hns3: make hclge_dbg_get_m7_stats_info static

hclge_dbg_get_m7_info is used only in the hclge_debugfs.c,
so it should be declared with static.

Signed-off-by: Guojia Liao <liaoguojia@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>