Input: atmel_mxt_ts - switch to use device_property_count_u32()

Use use device_property_count_u32() directly, that makes code neater.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/atmel_mxt_ts.c

@@ -2990,8 +2990,7 @@ static int mxt_parse_device_properties(struct mxt_data *data)
 	int error;
 
 	if (device_property_present(dev, keymap_property)) {
-		n_keys = device_property_read_u32_array(dev, keymap_property,
-							NULL, 0);
+		n_keys = device_property_count_u32(dev, keymap_property);
 		if (n_keys <= 0) {
 			error = n_keys < 0 ? n_keys : -EINVAL;
 			dev_err(dev, "invalid/malformed '%s' property: %d\n",