ARM: dts: meson8b: ec100: enable the Ethernet PHY interrupt

The INTR32 pin of the IP101GR Ethernet PHY is routed to the GPIOH_3 pad
on the SoC.
Enable the interrupt function of the PHY's INTR32 pin to switch it from
it's default "receive error" mode to "interrupt pin" mode.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>