drivers: ethernet: remove phy related configs from eth config

remove phy related configs from eth config.
phy related configs chould go directly into the phy.
Most ethernet drivers didn't support the now removed
functions yet. Users should instead use `phy_configure_link()`
together with the `net_eth_get_phy()` function.

Signed-off-by: Fin Maaß <f.maass@vogl-electronic.com>