AK2: allow U-Boot uImage without ramdisk

tools/ak2-core.sh

@@ -53,9 +53,8 @@ split_boot() {
     test $? != 0 && dumpfail=1;
     if [ "$(cat $split_img/boot.img-type)" == "Multi" ]; then
       $bin/dumpimage -i /tmp/anykernel/boot.img -p 1 $split_img/boot.img-ramdisk.gz;
-    else
-      dumpfail=1;
     fi;
+    test $? != 0 && dumpfail=1;
   elif [ -f "$bin/rkcrc" ]; then
     dd bs=4096 skip=8 iflag=skip_bytes conv=notrunc if=/tmp/anykernel/boot.img of=$split_img/boot.img-ramdisk.gz;
   elif [ -f "$bin/pxa-unpackbootimg" ]; then
@@ -219,7 +218,8 @@ flash_boot() {
     esac;
   fi;
   if [ -f "$bin/mkimage" ]; then
-    $bin/mkimage -A $arch -O $os -T $type -C $comp -a $addr -e $ep -n "$name" -d $kernel:$rd boot-new.img;
+    test "$type" == "Multi" && uramdisk=":$rd";
+    $bin/mkimage -A $arch -O $os -T $type -C $comp -a $addr -e $ep -n "$name" -d $kernel$uramdisk boot-new.img;
   elif [ -f "$bin/elftool" ]; then
     $bin/elftool pack -o boot-new.img header=$split_img/boot.img-header $kernel $rd,ramdisk $rpm $split_img/boot.img-cmdline@cmdline;
   elif [ -f "$bin/rkcrc" ]; then