net: fec: Reset ethernet PHY whenever the enet_out clock is being enabled
If a PHY uses ENET_OUT as reference clock, it may need a RESET to get
functional after the clock had been disabled.
Failure to do this results in the link state constantly toggling
between up and down:
fec
02188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
fec
02188000.ethernet eth0: Link is Down
fec
02188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
fec
02188000.ethernet eth0: Link is Down
[...]
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>