ARM: dts: sun7i: bananapi: Enable RGMII RX/TX delay on Ethernet PHY

The Ethernet PHY on the Bananapi M1 has the RX and TX delays enabled on
the PHY, using pull-ups on the RXDLY and TXDLY pins.

Fix the phy-mode description to correct reflect this so that the
implementation doesn't reconfigure the delays incorrectly. This
happened with commit bbc4d71d ("net: phy: realtek: fix rtl8211e
rx/tx delay config").

Fixes: 8a5b272f ("ARM: dts: sun7i: Add Banana Pi board")
Signed-off-by: Pablo Greco <pgreco@centosproject.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/1604326600-39544-1-git-send-email-pgreco@centosproject.org