net: thunderx: convert to use ndo_hwtstamp callbacks

net: thunderx: convert to use ndo_hwtstamp callbacks

The driver implemented SIOCSHWTSTAMP ioctl command only, but it also
stores configuration in private data, so it's possible to report it back
to users. Implement both ndo_hwtstamp_set and ndo_hwtstamp_get
callbacks.

Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20251103150952.3538205-6-vadim.fedorenko@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>