sfc-siena: Implement ndo_hwtstamp_(get|set)

Update efx->ptp_data to use kernel_hwtstamp_config and implement
ndo_hwtstamp_(get|set). Remove SIOCGHWTSTAMP and SIOCSHWTSTAMP from
efx_ioctl.

Signed-off-by: Alex Austin <alex.austin@amd.com>
Acked-by: Martin Habets <habetsm.xilinx@gmail.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20231130135826.19018-3-alex.austin@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

sfc/siena: Rename peripheral functions to avoid conflicts with sfc

For siena use efx_siena_ as the function prefix.
This patch covers selftest.h, ptp.h, net_driver.h and ethtool_common.h.
efx_ethtool_fill_self_tests() can become static.
Some functions in ptp.c can also become static.
Rename loopback_mode in net_driver.h.

Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

sfc: Copy shared files needed for Siena (part 2)

These are the files starting with m through w.
No changes are done, those will be done with subsequent commits.

Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>