Merge branch 'idpf-add-get-set-for-ethtool-s-header-split-ringparam'

Alexander Lobakin says:

====================
idpf: add get/set for Ethtool's header split ringparam

Currently, the header split feature (putting headers in one smaller
buffer and then the data in a separate bigger one) is always enabled
in idpf when supported.
One may want to not have fragmented frames per each packet, for example,
to avoid XDP frags. To better optimize setups for particular workloads,
add ability to switch the header split state on and off via Ethtool's
ringparams, as well as to query the current status.
There's currently only GET in the Ethtool Netlink interface for now,
so add SET first. I suspect idpf is not the only one supporting this.
====================

Link: https://lore.kernel.org/r/20231212142752.935000-1-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>