net: phy: vitesse: implement MDI-X configuration in vsc73xx

This commit introduces MDI-X configuration support in vsc73xx phys.

Vsc73xx supports only auto mode or forced MDI.

Vsc73xx have auto MDI-X disabled by default in forced speed mode.
This commit enables it.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20240826093710.511837-1-paweldembicki@gmail.com


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