Update moby tool and qemu fixes

- no longer uses several of the `mkimage-*` tools in favour of dogfooding
with `linuxkit` and using the `mkimage` package.
- fix the qemu docker container fallbacks to work better when multiple
paths are used for disks and the image.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

tools/mkimage-gcp/make-gcp

@@ -1,55 +0,0 @@
-#!/bin/sh
-
-set -e
-
-mkdir -p /tmp/image
-cd /tmp/image
-
-# input is a tarball of kernel and initrd.img on stdin
-# output is a compressed tarball of a raw disk image on stdout
-
-mkdir -p files
-
-cd files
-
-# extract. As guestfs base is currently Debian, no compression support
-# only if stdin is a tty, if so need files volume mounted...
-[ -t 0 ] || tar xf -
-
-INITRD="$(find . -name '*.img')"
-KERNEL="$(find . -name kernel -or -name bzImage)"
-CMDLINE="$*"
-
-[ "$KERNEL" = "./kernel" ] || mv "$KERNEL" kernel
-[ "$INITRD" = "./initrd.img" ] || mv "$INITRD" initrd.img
-
-# clean up subdirectories
-find . -mindepth 1 -maxdepth 1 -type d | xargs rm -rf
-
-# should be externally provided as GCP specific
-GCP_CONFIG="earlyprintk=ttyS0,115200 console=ttyS0,115200 vsyscall=emulate page_poison=1"
-
-CFG="DEFAULT linux
-LABEL linux
-    KERNEL /kernel
-    INITRD /initrd.img
-    APPEND ${CMDLINE}
-"
-
-printf "$CFG" > syslinux.cfg
-
-cd ..
-
-tar cf files.tar -C files .
-
-virt-make-fs --size=1G --type=ext4 --partition files.tar disk.raw
-
-guestfish -a disk.raw -m /dev/sda1 <<EOF
-  upload /usr/lib/SYSLINUX/mbr.bin /mbr.bin
-  copy-file-to-device /mbr.bin /dev/sda size:440
-  rm /mbr.bin
-  extlinux /
-  part-set-bootable /dev/sda 1 true
-EOF
-
-tar cf - disk.raw | gzip -9