generic-adc-battery: Fix checking if none of the channels are supported

If none of the channels are supported, index is 0. Also ensure to return
error code instead of 0 in goto second_mem_fail path.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: anish kumar <anish198519851985@gmail.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>

drivers/power/generic-adc-battery.c

@@ -299,8 +299,10 @@ static int gab_probe(struct platform_device *pdev)
 	}
 
 	/* none of the channels are supported so let's bail out */
-	if (index == ARRAY_SIZE(gab_chan_name))
+	if (index == 0) {
+		ret = -ENODEV;
 		goto second_mem_fail;
+	}
 
 	/*
 	 * Total number of properties is equal to static properties