Dove: activate GPIO interrupts in DT

In a DT, the interrupts of an interrupt-controller are not usable when
#interrupt-cells is missing.

This patch activates the interrupts of the GPIOs 0 and 1 for the Marvell
Dove SoC.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>