Input: goodix - support Goodix gt5688

From what I've seen in vendor trees it's fine to treat this as gt1x¹.
Tested on the Purism Librem 5 Devkit (Rocktech JH057N00900 panel).

[1]: https://github.com/TadiT7/android_kernel_mtk-4.4/tree/master/drivers/input/touchscreen/mediatek/GT5688Signed-off-by: Guido Günther <agx@sigxcpu.org>
Reviewed-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/goodix.txt

@@ -3,6 +3,7 @@ Device tree bindings for Goodix GT9xx series touchscreen controller
 Required properties:
 
  - compatible		: Should be "goodix,gt1151"
+				 or "goodix,gt5688"
 				 or "goodix,gt911"
 				 or "goodix,gt9110"
 				 or "goodix,gt912"

drivers/input/touchscreen/goodix.c

@@ -216,6 +216,7 @@ static const struct goodix_chip_data *goodix_get_chip_data(u16 id)
 {
 	switch (id) {
 	case 1151:
+	case 5688:
 		return &gt1x_chip_data;
 
 	case 911:
@@ -942,6 +943,7 @@ MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
 #ifdef CONFIG_OF
 static const struct of_device_id goodix_of_match[] = {
 	{ .compatible = "goodix,gt1151" },
+	{ .compatible = "goodix,gt5688" },
 	{ .compatible = "goodix,gt911" },
 	{ .compatible = "goodix,gt9110" },
 	{ .compatible = "goodix,gt912" },