realtek: build factory images for all DGS-1210 models

Currently we build factory images only for DGS-1210-28 model. Relax
that constraint and take care about all models. Tested on DGS-1210-20
and should work on other models too because of common flash layout.
Tested-by: NLuiz Angelo Daros de Luca <luizluca@gmail.com>
Signed-off-by: NMarkus Stockhausen <markus.stockhausen@gmx.de>
(cherry picked from commit 2b49ec3a)

target/linux/realtek/image/rtl838x.mk

@@ -17,6 +17,13 @@ define Device/d-link_dgs-1210
   DEVICE_VENDOR := D-Link
   DLINK_KERNEL_PART_SIZE := 1572864
   KERNEL := kernel-bin | append-dtb | gzip | uImage gzip | dlink-cameo
+  CAMEO_KERNEL_PART := 2
+  CAMEO_ROOTFS_PART := 3
+  CAMEO_CUSTOMER_SIGNATURE := 2
+  CAMEO_BOARD_VERSION := 32
+  IMAGES += factory_image1.bin
+  IMAGE/factory_image1.bin := append-kernel | pad-to 64k | \
+	append-rootfs | pad-rootfs | pad-to 16 | check-size | dlink-headers
 endef
 
 define Device/d-link_dgs-1210-10p
@@ -35,13 +42,6 @@ TARGET_DEVICES += d-link_dgs-1210-16
 define Device/d-link_dgs-1210-28
   $(Device/d-link_dgs-1210)
   DEVICE_MODEL := DGS-1210-28
-  CAMEO_KERNEL_PART := 2
-  CAMEO_ROOTFS_PART := 3
-  CAMEO_CUSTOMER_SIGNATURE := 2
-  CAMEO_BOARD_VERSION := 32
-  IMAGES += factory_image1.bin
-  IMAGE/factory_image1.bin := append-kernel | pad-to 64k | \
-        append-rootfs | pad-rootfs | pad-to 16 | check-size | dlink-headers
 endef
 TARGET_DEVICES += d-link_dgs-1210-28