Input: ads7846 - change name of wakeup property to "wakeup-source"

Wakeup property of device is not Linux-specific, it describes intended
system behavior regardless of the OS being used. Therefore let's drop
"linux," prefix, and, while at it, use the same name as I2C bus does:
"wakeup-source".

We keep parsing old name to keep compatibility with old DTSes.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/ads7846.txt

@@ -64,7 +64,7 @@ Optional properties:
 					pendown-gpio (u32).
 	pendown-gpio			GPIO handle describing the pin the !PENIRQ
 					line is connected to.
-	linux,wakeup			use any event on touchscreen as wakeup event.
+	wakeup-source			use any event on touchscreen as wakeup event.
 
 
 Example for a TSC2046 chip connected to an McSPI controller of an OMAP SoC::

drivers/input/touchscreen/ads7846.c

@@ -1234,7 +1234,8 @@ static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
 	of_property_read_u32(node, "ti,pendown-gpio-debounce",
 			     &pdata->gpio_pendown_debounce);
 
-	pdata->wakeup = of_property_read_bool(node, "linux,wakeup");
+	pdata->wakeup = of_property_read_bool(node, "wakeup-source") ||
+			of_property_read_bool(node, "linux,wakeup");
 
 	pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0);