mediatek: bpi-r64: fix sdcard.img.gz in ImageBuilder

Generating the sdcard.img.gz file requires the initramfs/recovery
image to be present. Use the newly introduced 'append-image-stage'
build command to fix the ImageBuilder for the BPi-R64.

Signed-off-by: Daniel Golle <[email protected]>

target/linux/mediatek/image/mt7622.mk

@@ -84,7 +84,7 @@ define Device/bananapi_bpi-r64
   ARTIFACT/sdcard.img.gz	:= mt7622-gpt sdmmc |\
 				   pad-to 512k | bl2 sdmmc-2ddr |\
 				   pad-to 2048k | bl31-uboot bananapi_bpi-r64-sdmmc |\
-				   pad-to 6144k | append-image initramfs-recovery.itb |\
+				   pad-to 6144k | append-image-stage initramfs-recovery.itb |\
 				   pad-to 38912k | mt7622-gpt emmc |\
 				   pad-to 39424k | bl2 emmc-2ddr |\
 				   pad-to 40960k | bl31-uboot bananapi_bpi-r64-emmc |\