scripts/ubinize-image.sh: add support for adding custom partitions

Signed-off-by: Felix Fietkau <nbd@nbd.name>

include/image-commands.mk

@@ -114,6 +114,7 @@ define Build/append-ubi
 	sh $(TOPDIR)/scripts/ubinize-image.sh \
 		$(if $(UBOOTENV_IN_UBI),--uboot-env) \
 		$(if $(KERNEL_IN_UBI),--kernel $(IMAGE_KERNEL)) \
+		$(foreach part,$(UBINIZE_PARTS),--part $(part)) \
 		$(IMAGE_ROOTFS) \
 		$@.tmp \
 		-p $(BLOCKSIZE) -m $(PAGESIZE) \

include/image.mk

@@ -347,6 +347,7 @@ define Device/Init
   SUBPAGESIZE :=
   VID_HDR_OFFSET :=
   UBINIZE_OPTS := -E 5
+  UBINIZE_PARTS :=
   MKUBIFS_OPTS :=
 
   FS_OPTIONS/ubifs = $$(MKUBIFS_OPTS)
@@ -365,7 +366,7 @@ DEFAULT_DEVICE_VARS := \
   DEVICE_DTS DEVICE_DTS_DIR BOARD_NAME CMDLINE \
   UBOOTENV_IN_UBI KERNEL_IN_UBI \
   BLOCKSIZE PAGESIZE SUBPAGESIZE VID_HDR_OFFSET \
-  UBINIZE_OPTS UIMAGE_NAME
+  UBINIZE_OPTS UIMAGE_NAME UBINIZE_PARTS
 
 define Device/ExportVar
   $(1) : $(2):=$$($(2))