Input: atmel_mxt_ts - add missing compatible strings to OF device table

Commit af503716ac14 ("i2c: core: report OF style module alias for devices
registered via OF") fixed how the I2C core reports the module alias when
devices are registered via OF.

But the atmel_mxt_ts driver only has an "atmel,maxtouch" compatible in its
OF device ID table, so if a Device Tree is using a different one, autoload
won't be working for the module (the matching works because the I2C device
ID table is used as a fallback).

So add compatible strings for each of the entries in the I2C device table.

Fixes: af503716ac14 ("i2c: core: report OF style module alias for devices registered via OF")
Reported-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
[dtor: document which compatibles are deprecated and should not be used]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/atmel,maxtouch.txt

@@ -4,6 +4,13 @@ Required properties:
 - compatible:
     atmel,maxtouch
 
+    The following compatibles have been used in various products but are
+    deprecated:
+	atmel,qt602240_ts
+	atmel,atmel_mxt_ts
+	atmel,atmel_mxt_tp
+	atmel,mXT224
+
 - reg: The I2C address of the device
 
 - interrupts: The sink for the touchpad's IRQ output

drivers/input/touchscreen/atmel_mxt_ts.c

@@ -3282,6 +3282,11 @@ static SIMPLE_DEV_PM_OPS(mxt_pm_ops, mxt_suspend, mxt_resume);
 
 static const struct of_device_id mxt_of_match[] = {
 	{ .compatible = "atmel,maxtouch", },
+	/* Compatibles listed below are deprecated */
+	{ .compatible = "atmel,qt602240_ts", },
+	{ .compatible = "atmel,atmel_mxt_ts", },
+	{ .compatible = "atmel,atmel_mxt_tp", },
+	{ .compatible = "atmel,mXT224", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, mxt_of_match);