make_image: Fake vmlinuz_hd.vblock on ARM.

build_kernel_image.sh

Index: build_kernel_image.sh
diff --git a/build_kernel_image.sh b/build_kernel_image.sh
index b4e393e9b5f8d0a0735e874fd58cb6a61910f555..55513e237a7d9e2ccbc8aae968292742d82529d3 100755
--- a/build_kernel_image.sh
+++ b/build_kernel_image.sh
@@ -226,6 +226,11 @@ elif [[ "${FLAGS_arch}" = "arm" ]]; then
   rm -f "${FLAGS_to}"
   dd if="${kernel_script_img}" of="${FLAGS_to}" bs=512 count="${script_size}"
   dd if="${kernel_image}" of="${FLAGS_to}" bs=512 seek="${script_size}"
+
+  # TODO: HACK: Until the kernel partition contains a signed image, create a
+  # phony hd.vblock to keep chromeos-install and cros_generate_update_paload
+  # working.
+  dd if="${FLAGS_to}" of="${FLAGS_hd_vblock}" bs=64K count=1
 else
   error "Unknown arch: ${FLAGS_arch}"
 fi