net: hns3: refactor the debugfs process

mainline inclusion
from mainline-v5.14-rc1
commit 5e69ea7e
category: feature
bugzilla: NA
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5e69ea7ee2a6



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Currently, each debugfs command needs to create a file to get
the information. To better support more debugfs commands, the
debugfs process is reconstructed, including the process of
creating dentries and files, and obtaining information.

Signed-off-by: Yufeng Mo <moyufeng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Reviewed-by: Junxin Chen <chenjunxin1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>