Introduce support for configuring the master/slave role of PHYs based on
the `timing-role` property in the device tree. While this functionality
is necessary for Single Pair Ethernet (SPE) PHYs (1000/100/10Base-T1)
where hardware strap pins may be unavailable or incorrectly set, it
works for any PHY type.
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>