net: micrel: Cable Diagnostics feature for lan8841 PHY

commit a98a6bc293fd03ab5e251b9dce65a96a4c154b94 from
https://github.com/linux4microchip/linux.git

 linux-6.1-mchp+fpga

Add support for cable diagnostics in lan8841 PHY. It has the same
registers layout as lan8814 PHY, therefore reuse the functionality.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230208114406.1666671-1-horatiu.vultur@microchip.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Saravanan.K.S <saravanan.kadambathursubramaniyam@windriver.com>