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/video/Kconfig b/drivers/video/Kconfig
index 3244cd7..5cb3685 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1,3 +1,9 @@
+#
+# Video configuration
+#
+
+menu "Graphics support"
+
 config VIDEO_VESA
 	bool "Enable VESA video driver support"
 	default n
@@ -242,3 +248,5 @@
 	   have an eDP display connected.
 
 source "drivers/video/bridge/Kconfig"
+
+endmenu