net: hns3: support set pfc pause trans time

driver inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I6W94W


CVE: NA

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The patch provides a customized interface to modify the pause trans time
and retains the configured parameters.

Signed-off-by: shaojijie <shaojijie@huawei.com>
Signed-off-by: Jiantao Xiao <xiaojiantao1@h-partners.com>