video: add an option for video simplefb via DT

Add an option to indicate that the video driver should setup a SimpleFB
node that passes the video framebuffer initialized by U-Boot to the
operating system kernel.

Currently only the Allwinner DE driver uses this option, and the
definition of this option in the sunxi-common.h config header is
converted to an imply of this option from CONFIG_VIDEO_SUNXI.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/mach-sunxi/Kconfig b/arch/arm/mach-sunxi/Kconfig
index 3c29fc6..33869a3 100644
--- a/arch/arm/mach-sunxi/Kconfig
+++ b/arch/arm/mach-sunxi/Kconfig
@@ -615,6 +615,7 @@
 	depends on !MACH_SUN9I
 	depends on !MACH_SUN50I
 	select VIDEO
+	imply VIDEO_DT_SIMPLEFB
 	default y
 	---help---
 	Say Y here to add support for using a cfb console on the HDMI, LCD