Merge branch 'net-lan966x-add-support-for-fdma'

Horatiu Vultur says:

====================
net: lan966x: Add support for FDMA

Currently when injecting or extracting a frame from CPU, the frame
is given to the HW each word at a time. There is another way to
inject/extract frames from CPU using FDMA(Frame Direct Memory Access).
In this way the entire frame is given to the HW. This improves both
RX and TX bitrate.
====================

Tested-by: Michael Walle <michael@walle.cc> # on kontron-kswitch-d10
Link: https://lore.kernel.org/r/20220408070357.559899-1-horatiu.vultur@microchip.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>