ice: implement ethtool standard stats

ice: implement ethtool standard stats

Add support for MAC/pause/RMON stats. This enables reporting hardware
statistics in a common way via:

ethtool -S eth0 --all-groups
and
ethtool --include-statistics --show-pause eth0

While doing so, add support for one new stat, receive length error
(RLEC), which is extremely unlikely to happen since most L2 frames have
a type/length field specifying a "type", and raw ethernet frames aren't
used much any longer.

NOTE: I didn't implement Ctrl aka control frame stats because the
hardware doesn't seem to implement support.

Reviewed-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Rinitha S <sx.rinitha@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20251016-jk-iwl-next-2025-10-15-v2-9-ff3a390d9fc6@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>