lantiq: add FRITZ7360SL phy reset gpios

Due to a hardware bug of Atheros 8030 phys, the driver need to reset
the phys on link state change.

Use the correct compatible string for the at903x phys connected to
switch port 0 and 1.

Fix the pinmux of the gpio lines connected to the reset pin of the phys
and define the reset-pins to let the driver do the fixups.

Fixes FS#343

Signed-off-by: Mathias Kresin <dev@kresin.me>