greybus: power_supply: do not release failed supply alloc

If allocation of memory for each supply fail, we should get out of
release any individual supply.
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Reported-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/power_supply.c

@@ -569,6 +569,9 @@ static void _gb_power_supplies_release(struct gb_power_supplies *supplies)
 {
 	int i;
 
+	if (!supplies->supply)
+		return;
+
 	mutex_lock(&supplies->supplies_lock);
 	for (i = 0; i < supplies->supplies_count; i++)
 		_gb_power_supply_release(&supplies->supply[i]);