dm: implement a Miscellaneous uclass

Implement a Miscellaneous uclass with generic read or
write operations. This class is used only for those
do not fit other more general classes.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 8d0fc3c..7e76b12 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -5,6 +5,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+obj-$(CONFIG_MISC) += misc-uclass.o
 obj-$(CONFIG_ALI152X) += ali512x.o
 obj-$(CONFIG_DS4510)  += ds4510.o
 obj-$(CONFIG_CBMEM_CONSOLE) += cbmem_console.o