net: phy: microchip_t1: Cable Diagnostics for lan887x

Add support for cable diagnostics in lan887x PHY.
Using this we can diagnose connected/open/short wires and
also length where cable fault is occurred.

Signed-off-by: Divya Koppera <divya.koppera@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20240909114339.3446-1-divya.koppera@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Divya-Koppera