Merge branch 'net-convert-drivers-to-get_rx_ring_count-last-part'

Breno Leitao says:

====================
net: convert drivers to .get_rx_ring_count (last part)

Commit 84eaf4359c36 ("net: ethtool: add get_rx_ring_count callback to
optimize RX ring queries") added specific support for GRXRINGS callback,
simplifying .get_rxnfc.

Remove the handling of GRXRINGS in .get_rxnfc() by moving it to the new
.get_rx_ring_count().

This simplifies the RX ring count retrieval and aligns the following
drivers with the new ethtool API for querying RX ring parameters.

 * sfc
 * ionic
 * sfc/siena
 * sfc/ef100
 * fbnic
 * mana
 * nfp
 * atlantic
 * benet (this is v2 in fact, where v1 had some discussions that
   required a v2). See link [0]

Link: https://lore.kernel.org/all/20260119094514.5b12a097@kernel.org/
This is covering the last drivers, and as soon as this lands, I will
change the ethtool framework to avoid calling .get_rx_ring_count for
ETHTOOL_GRXRINGS, simplifying the ethtool core framework.
====================

Link: https://patch.msgid.link/20260122-grxring_big_v4-v2-0-94dbe4dcaa10@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>