Rework build process to work for non-root users.

Find alternative ways to create the same effect for each step of
the setup without being able to use a Linux-based `chroot(8)`
environment.  This includes working around calling the `mkinitfs`
script for building the initramfs, and replacing it with a specific
list of files to be added.

2 files changed, 72 insertions, 28 deletions

diff --git a/guest/initrd.files b/guest/initrd.files
new file mode 100644
index 0000000..7ed354c
--- /dev/null
+++ b/guest/initrd.files
@@ -0,0 +1,72 @@
+bin/sh
+bin/busybox
+bin/kmod
+sbin/apk
+sbin/modprobe
+sbin/nlplug-findfs
+lib/libuuid.so.*
+lib/libblkid.so.*
+lib/libcryptsetup.so.*
+lib/libz.so.*
+lib/libuuid.so.*
+lib/libc.musl-x86_64.so.*
+lib/firmware
+lib/libssl.so.*
+lib/libkmod.so.*
+lib/modules/*/modules.dep.bin
+lib/modules/*/kernel/net/core/failover.ko.gz
+lib/modules/*/kernel/drivers/net/virtio_net.ko.gz
+lib/modules/*/kernel/drivers/net/net_failover.ko.gz
+lib/modules/*/kernel/drivers/vdpa/vdpa.ko.gz
+lib/modules/*/kernel/drivers/block/loop.ko.gz
+lib/modules/*/kernel/drivers/block/virtio_blk.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_ring.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_dma_buf.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_balloon.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_input.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_pci_modern_dev.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_pci.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_mmio.ko.gz
+lib/modules/*/kernel/drivers/virtio/virtio_vdpa.ko.gz
+lib/modules/*/kernel/fs/overlayfs/overlay.ko.gz
+lib/modules/*/kernel/fs/squashfs/squashfs.ko.gz
+lib/modules/*/modules.builtin
+lib/modules/*/modules.devname
+lib/modules/*/modules.dep
+lib/modules/*/modules.symbols.bin
+lib/modules/*/modules.symbols
+lib/modules/*/modules.softdep
+lib/modules/*/modules.alias
+lib/modules/*/modules.builtin.alias.bin
+lib/modules/*/modules.alias.bin
+lib/modules/*/modules.builtin.bin
+lib/modules/*/modules.order
+lib/ld-musl-x86_64.so.*
+lib/libapk.so.*
+lib/libz.so.*
+lib/libkmod.so.*
+lib/libcrypto.so.*
+lib/libdevmapper.so.*
+lib/mdev/usbdev
+lib/mdev/dvbdev
+lib/mdev/persistent-storage
+lib/libcryptsetup.so.*
+lib/libblkid.so.*
+proc
+dev
+media/floppy
+media/cdrom
+media/usb
+run
+etc/apk/keys/alpine-devel@lists.alpinelinux.org-*.rsa.pub
+etc/mdev.conf
+etc/modprobe.d/*.conf
+usr/lib/liblzma.so.*
+usr/lib/libjson-c.so.*
+usr/lib/libzstd.so.*
+usr/lib/libzstd.so.*
+usr/lib/libargon2.so.*
+usr/lib/liblzma.so.*
+usr/lib/libjson-c.so.*
+sys
diff --git a/guest/setup.sh b/guest/setup.sh
deleted file mode 100644
index 9ac748b..0000000
--- a/guest/setup.sh
+++ /dev/null
@@ -1,28 +0,0 @@
-apk add \
-    --no-network \
-    --force-non-repository \
-    /packages/*.apk
-passwd -d root
-ln -s /dev/null /root/.ash_history
-ln -s /tmp/resolv.conf /etc
-rm /etc/motd
-rc-update add networking boot
-rc-update add urandom boot
-rc-update add bootmisc boot
-rc-update add acpid default
-rc-update add modules boot
-rc-update add crond default
-rc-update add devfs sysinit
-rc-update add dmesg sysinit
-rc-update add hostname boot
-rc-update add hwclock boot
-rc-update add hwdrivers sysinit
-rc-update add iptables default
-rc-update add mdev sysinit
-rc-update add sysctl boot
-rc-update add syslog boot
-rc-update add udhcpd default
-rc-update add wpa_supplicant boot
-rc-update add wpa_passthru boot
-mkdir -p /media/etc
-mkdir -p /media/wpa