Convert CONFIG_VIDEO to Kconfig

This converts the following to Kconfig:
   CONFIG_VIDEO

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Jagan Teki <jteki@openedev.com>
diff --git a/configs/mt_ventoux_defconfig b/configs/mt_ventoux_defconfig
index 0fdec87..39773e7 100644
--- a/configs/mt_ventoux_defconfig
+++ b/configs/mt_ventoux_defconfig
@@ -2,6 +2,7 @@
 CONFIG_OMAP34XX=y
 # CONFIG_SPL_EXT_SUPPORT is not set
 CONFIG_TARGET_MT_VENTOUX=y
+CONFIG_VIDEO=y
 CONFIG_FIT=y
 CONFIG_BOOTDELAY=10
 CONFIG_SPL=y