How to restore the MBR after do-release-upgrade?

[Ralf Mardorf]

PS:

There seems to be a version mismatch, so most likely a part
of Grub2 was restored.

  [root at moonstudio src]# ./bootinfoscript /tmp/bootinfo.txt 

  Boot Info Script 0.61      [1 April 2012]
  [snip]
  [root at moonstudio src]# grep Grub2 -A2 /tmp/bootinfo.txt 
   => Grub2 (v1.99) is installed in the MBR of /dev/sda and looks at
  sector 1 of the same hard drive for core.img. core.img is at this
  location and looks in partition 97 for .

Between "97" and the "." there unlikely should be just a space.

  [root at moonstudio src]# dpkg -l grub-pc | grep ii
  ii  grub-pc        2.02~beta2-36ubuntu3 amd64        GRand Unified
  Bootloader, version 2 (PC/BIOS version)