net: hns3: add hwtstamp_get/hwtstamp_set ops

net: hns3: add hwtstamp_get/hwtstamp_set ops

And .ndo_hwtstamp_get()/.ndo_hwtstamp_set() callbacks to HNS3 framework
to support HW timestamp configuration via netlink and adopt hns3pf to
use .ndo_hwtstamp_get()/.ndo_hwtstamp_set() callbacks.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jijie Shao <shaojijie@huawei.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20251023220457.3201122-7-vadim.fedorenko@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>