rockchip: dm: prepare rkmtd UCLASS

Prepare a rkmtd UCLASS in use for writing Rockchip boot blocks
in combination with existing userspace tools and rockusb command.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index a6045f5..5271e64 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -121,6 +121,7 @@
 	UCLASS_REGULATOR,	/* Regulator device */
 	UCLASS_REMOTEPROC,	/* Remote Processor device */
 	UCLASS_RESET,		/* Reset controller device */
+	UCLASS_RKMTD,		/* Rockchip MTD device */
 	UCLASS_RNG,		/* Random Number Generator */
 	UCLASS_RTC,		/* Real time clock device */
 	UCLASS_SCMI_AGENT,	/* Interface with an SCMI server */