MIPS: jz4740: Fix surviving instance of irq_to_gpio()

This is fallout from commit 832f5dacfa0b ("MIPS: Remove all the uses of
custom gpio.h").

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Suggested-by: Lars-Peter Clausen <lars@metafoo.de>
1 file changed