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/aristainetos2c_defconfig b/configs/aristainetos2c_defconfig
index 7c421f5..3f6f579 100644
--- a/configs/aristainetos2c_defconfig
+++ b/configs/aristainetos2c_defconfig
@@ -113,7 +113,7 @@
 CONFIG_SYSRESET_WATCHDOG=y
 CONFIG_USB=y
 CONFIG_USB_STORAGE=y
-CONFIG_DM_VIDEO=y
+CONFIG_VIDEO=y
 CONFIG_VIDEO_LOGO=y
 CONFIG_SYS_WHITE_ON_BLACK=y
 CONFIG_DISPLAY=y