rockchip: require image metadata

All devices in the rockchip target have appended image-metadata. Enforce
the presence of this metadata to avoid flashing incomplete images.

This is the de-facto standard for almost all OpenWrt targets.

Signed-off-by: David Bauer <[email protected]>

target/linux/rockchip/armv8/base-files/lib/upgrade/platform.sh

@@ -1,3 +1,5 @@
+REQUIRE_IMAGE_METADATA=1
+
 platform_check_image() {
 	local diskdev partdev diff