video: Rename CONFIG_DM_VIDEO to CONFIG_VIDEO

Now that all the old code is gone, rename this option. Driver model
migration is now complete.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/evb-rk3288_defconfig b/configs/evb-rk3288_defconfig
index 40e235b..1838447 100644
--- a/configs/evb-rk3288_defconfig
+++ b/configs/evb-rk3288_defconfig
@@ -86,7 +86,7 @@
 CONFIG_ROCKCHIP_USB2_PHY=y
 CONFIG_USB_GADGET=y
 CONFIG_USB_GADGET_DWC2_OTG=y
-CONFIG_DM_VIDEO=y
+CONFIG_VIDEO=y
 # CONFIG_VIDEO_BPP8 is not set
 CONFIG_DISPLAY=y
 CONFIG_VIDEO_ROCKCHIP=y