collie_battery: Get rid of irq_to_gpio usage

Since 9d08d5d77a355510c2f5657c86b0a4b25acfe72c, irq_to_gpio() is no
longer available but still in use by collie_battery.c. As it's just
for a debug message, just get rid of this call.

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
diff --git a/drivers/power/collie_battery.c b/drivers/power/collie_battery.c
index 548d263..7a40fce 100644
--- a/drivers/power/collie_battery.c
+++ b/drivers/power/collie_battery.c
@@ -146,7 +146,7 @@
 
 static irqreturn_t collie_bat_gpio_isr(int irq, void *data)
 {
-	pr_info("collie_bat_gpio irq: %d\n", gpio_get_value(irq_to_gpio(irq)));
+	pr_info("collie_bat_gpio irq\n");
 	schedule_work(&bat_work);
 	return IRQ_HANDLED;
 }