Enable FPGA's IRQ controller. It is in charge of dispatching interrupts
generated by IPs in the FPGA. The SoC is notified that an interrupt
occurred through a GPIO.
Signed-off-by: NDamien Riegel <damien.riegel@savoirfairelinux.com>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>