ar71xx: enable nand-utils in the mikrotik subtarget to ensure it makes it to initramfs

Without it, sysupgrade from initramfs to nand fails

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

target/linux/ar71xx/image/mikrotik.mk

 define Device/mikrotik
   PROFILES := Default
-  DEVICE_PACKAGES := kmod-usb-core kmod-usb-ohci kmod-usb2 kmod-usb-ledtrig-usbport nand-utils
+  DEVICE_PACKAGES := kmod-usb-core kmod-usb-ohci kmod-usb2 kmod-usb-ledtrig-usbport
   BOARD_NAME := routerboard
   KERNEL_INITRAMFS :=
   KERNEL_NAME := loader-generic.elf
@@ -26,7 +26,7 @@ TARGET_DEVICES += nand-64m nand-large
 
 define Device/rb-nor-flash-16M
   DEVICE_TITLE := MikroTik RouterBoard with 16 MB SPI NOR flash
-  DEVICE_PACKAGES := rbcfg rssileds
+  DEVICE_PACKAGES := rbcfg rssileds -nand-utils
   IMAGE_SIZE := 16000k
   LOADER_TYPE := elf
   KERNEL_INSTALL := 1

target/linux/ar71xx/mikrotik/target.mk

 BOARDNAME:=Mikrotik devices with NAND/NOR flash
 FEATURES += squashfs ramdisk minor nand
 
+DEFAULT_PACKAGES += nand-utils
+
 define Target/Description
 	Build firmware images for Atheros AR71xx/AR913x based Mikrotik boards.
 	e.g. MikroTik RB-4xx or RB-750