drivers: hierarchize drivers Kconfig menu

The menuconfig for drivers are getting more and more cluttered
and unreadable because too many entries are displayed in a single
flat menu.  Use hierarchic menu for each category.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: Update to apply again in a few places, drop USB hunk]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 3b7f76a..f29a169 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -1,3 +1,9 @@
+#
+# Multifunction miscellaneous devices
+#
+
+menu "Multifunction device drivers"
+
 config CMD_CROS_EC
 	bool "Enable crosec command"
 	depends on CROS_EC
@@ -82,3 +88,5 @@
 	  Each driver can provide a reset method which will be called to
 	  effect a reset. The uclass will try all available drivers when
 	  reset_walk() is called.
+
+endmenu