image.mk: initialize BOARD_NAME and IMAGES, add it to DEVICE_VARS

Signed-off-by: Felix Fietkau <[email protected]>

include/image.mk

@@ -276,6 +276,7 @@ define Device/Init
   KERNEL_SIZE:=
   CMDLINE:=
 
+  IMAGES :=
   IMAGE_PREFIX := $(IMG_PREFIX)-$(1)
   IMAGE_NAME = $$(IMAGE_PREFIX)-$$(1)-$$(2)
   KERNEL_PREFIX = $$(IMAGE_PREFIX)
@@ -304,12 +305,14 @@ define Device/Init
   DEVICE_DTS :=
   DEVICE_DTS_DIR :=
 
+  BOARD_NAME :=
+
   FILESYSTEMS := $(TARGET_FILESYSTEMS)
 endef
 
 DEFAULT_DEVICE_VARS := \
   DEVICE_NAME KERNEL KERNEL_INITRAMFS KERNEL_INITRAMFS_IMAGE \
-  DEVICE_DTS DEVICE_DTS_DIR \
+  DEVICE_DTS DEVICE_DTS_DIR BOARD_NAME \
   UBOOTENV_IN_UBI KERNEL_IN_UBI \
   BLOCKSIZE PAGESIZE SUBPAGESIZE VID_HDR_OFFSET \
   UBINIZE_OPTS