mfd: Add missed free_irq in da903x_remove

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/da903x.c b/drivers/mfd/da903x.c
index 1b79c37..62ce685 100644
--- a/drivers/mfd/da903x.c
+++ b/drivers/mfd/da903x.c
@@ -549,6 +549,7 @@
 	struct da903x_chip *chip = i2c_get_clientdata(client);
 
 	da903x_remove_subdevs(chip);
+	free_irq(client->irq, chip);
 	kfree(chip);
 	return 0;
 }