Otherwise, an inserted SD card will look for a partition with the
reformsdboot and reformsdroot label, find it on the emmc and use those
instead of sd-card.

reform-check: check for old /etc/flash-kernel/preboot.d/00reform2_preboot overwriting /usr/share/flash-kernel/preboot.d/00reform2_preboot

 - support all combinations of:
    * new root partition is already mounted as /
    * new root partition lives elsewhere
    * new /boot partition is the same as the already configured one
    * new /boot is already mounted
    * new /boot device doesn't exist
 - error out if anything is still mounted that shouldn't be mounted
 - only mount when necessary
 - only use chroot if new root device is not /
 - use traps to always unmount everything and clean tmpfiles upon
   failure
 - consult /etc/fstab of new root for location of old /boot
 - copy over contents of old /boot to new one if necessary

Installing the mdadm package disables the wm8960audio sound card with these
errors on dmesg:
  fsl-sai 308b0000.sai: Missing dma channel for stream: 0
  fsl-sai 308b0000.sai: ASoC: error at snd_soc_pcm_component_new on 308b0000.sai: -22
  fsl-asoc-card sound: ASoC: can't create pcm HiFi :-22
  fsl-asoc-card sound: error -EINVAL: snd_soc_register_card failed
  fsl-asoc-card: probe of sound failed with error -22
It is not clear why this happens and the proper solution needs more
investigation. Until then, disabling the raid456 module will restore audio
at the cost of disabling raid.

install /usr/share/initramfs-tools/scripts/init-top/reform as a temporary workaround to mxsfb producing a blank screen on roughly 50% of boots