ARM: dts: imx6qdl-kontron-samx6i: fix phy-mode

commit 0df3c7d7 upstream.

The i.MX6 cannot add any RGMII delays. The PHY has to add both the RX
and TX delays on the RGMII interface. Fix the interface mode. While at
it, use the new phy-connection-type property name.

Fixes: 5694eed9 ("ARM: dts: imx6qdl-kontron-samx6i: move phy reset into phy-node")
Signed-off-by: Michael Walle <mwalle@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>