net: Implement missing SO_TIMESTAMPING_NEW cmsg support

[ Upstream commit 382a3201 ]

Commit 9718475e ("socket: Add SO_TIMESTAMPING_NEW") added the new
socket option SO_TIMESTAMPING_NEW. However, it was never implemented in
__sock_cmsg_send thus breaking SO_TIMESTAMPING cmsg for platforms using
SO_TIMESTAMPING_NEW.

Fixes: 9718475e

 ("socket: Add SO_TIMESTAMPING_NEW")
Link: https://lore.kernel.org/netdev/6a7281bf-bc4a-4f75-bb88-7011908ae471@app.fastmail.com/
Signed-off-by: Thomas Lange <thomas@corelatus.se>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240104085744.49164-1-thomas@corelatus.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>