mfd: palmas: Reset pm_power_off if it is set for the device

If Palams supports the system power controller and pm_power_off
is implemented through the Palmas driver then reset the pm_power_off
in driver remove.

This will avoid the call of Palmas driver after removal of driver.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/palmas.c b/drivers/mfd/palmas.c
index 3b63139..6aab016 100644
--- a/drivers/mfd/palmas.c
+++ b/drivers/mfd/palmas.c
@@ -570,6 +570,11 @@
 
 	regmap_del_irq_chip(palmas->irq, palmas->irq_data);
 
+	if (palmas == palmas_dev) {
+		pm_power_off = NULL;
+		palmas_dev = NULL;
+	}
+
 	return 0;
 }