Comment 7 for bug 1532355

This looks like a failure in the plymouth hook:

  run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.3.0-5-generic /boot/vmlinuz-4.3.0-5-generic
  update-initramfs: Generating /boot/initrd.img-4.3.0-5-generic
  sed: can't read /usr/share/plymouth/themes/ubuntu-text/ubuntu-text.plymouth: No such file or directory
  E: /usr/share/initramfs-tools/hooks/plymouth failed with return 2.
  update-initramfs: failed for /boot/initrd.img-4.3.0-5-generic with 2.
  run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 2
  Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-4.3.0-5-generic.postinst line 1025.