Input: ad7879 - pass up error codes from probe functions

If the sub-probe functions fail, we need to pass up the error code to the
higher levels from the probe function. We currently always return 0 even
if there was an error so higher levels don't report problems.

Signed-off-by: Michael Hennerich <[e-mail]>
Signed-off-by: Mike Frysinger <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/touchscreen/ad7879.c

···
 		kfree(ts);
 	}
 
-	return 0;
+	return error;
 }
 
 static int __devexit ad7879_remove(struct spi_device *spi)
···
 		kfree(ts);
 	}
 
-	return 0;
+	return error;
 }
 
 static int __devexit ad7879_remove(struct i2c_client *client)