platform/x86: surface3_button: Propagate error from gpiod_count()

Since gpiod_count() does not return 0 anymore, we don't need to shadow
its error code and would safely propagate to the user.

While here, replace second parameter by NULL in order to prevent side
effects on _DSD enabled firmware.

Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/platform/x86/surface3_button.c

@@ -196,9 +196,10 @@ static int surface3_button_probe(struct i2c_client *client,
 		    strlen(SURFACE_BUTTON_OBJ_NAME)))
 		return -ENODEV;
 
-	if (gpiod_count(dev, KBUILD_MODNAME) <= 0) {
+	error = gpiod_count(dev, NULL);
+	if (error < 0) {
 		dev_dbg(dev, "no GPIO attached, ignoring...\n");
-		return -ENODEV;
+		return error;
 	}
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);