power_supply: Add "unknown" in power supply type

For the default value of power supply type, "unknown" is added.
With default prop value, supply type property can be displayed
as default - "Unknown".
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

drivers/power/power_supply_sysfs.c

@@ -42,7 +42,7 @@ static ssize_t power_supply_show_property(struct device *dev,
 					  struct device_attribute *attr,
 					  char *buf) {
 	static char *type_text[] = {
-		"Battery", "UPS", "Mains", "USB",
+		"Unknown", "Battery", "UPS", "Mains", "USB",
 		"USB_DCP", "USB_CDP", "USB_ACA"
 	};
 	static char *status_text[] = {

include/linux/power_supply.h

@@ -123,7 +123,8 @@ enum power_supply_property {
 };
 
 enum power_supply_type {
-	POWER_SUPPLY_TYPE_BATTERY = 0,
+	POWER_SUPPLY_TYPE_UNKNOWN = 0,
+	POWER_SUPPLY_TYPE_BATTERY,
 	POWER_SUPPLY_TYPE_UPS,
 	POWER_SUPPLY_TYPE_MAINS,
 	POWER_SUPPLY_TYPE_USB,		/* Standard Downstream Port */