dm: video: Add a uclass for display port

eDP (Embedded DisplayPort) is a standard widely used in laptops to drive
LCD panels. Add a uclass for this which supports a few simple operations.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index b17528d..095bcb2 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -27,6 +27,7 @@
 	/* U-Boot uclasses start here - in alphabetical order */
 	UCLASS_CPU,		/* CPU, typically part of an SoC */
 	UCLASS_CROS_EC,		/* Chrome OS EC */
+	UCLASS_DISPLAY_PORT,	/* Display port video */
 	UCLASS_ETH,		/* Ethernet device */
 	UCLASS_GPIO,		/* Bank of general-purpose I/O pins */
 	UCLASS_I2C,		/* I2C bus */