net: phy: at803x: disable delay only for RGMII mode

net: phy: at803x: disable delay only for RGMII mode

Per "Documentation/devicetree/bindings/net/ethernet.txt" RGMII mode
should not have delay in PHY whereas RGMII_ID and RGMII_RXID/RGMII_TXID
can have delay in PHY.

So disable the delay only for RGMII mode and enable for other modes.
Also treat the default case as disabled delays.

Fixes: cd28d1d6e52e: ("net: phy: at803x: Disable phy delay for RGMII mode")
Reported-by: Peter Ujfalusi <[email protected]>
Reviewed-by: Niklas Cassel <[email protected]>
Tested-by: Peter Ujfalusi <[email protected]>
Signed-off-by: Vinod Koul <[email protected]>
Signed-off-by: David S. Miller <[email protected]>