convert-to-edition: Remove call to grub2-mkconfig
This was done to ensure that the grub menu showed the newly set
edition was properly displayed, but it potentially carries side
effects for some custom setups. Since it was purely aesthetic, this
patch will remove it until we come up with a better solution.
Subsequent kernel updates will still show the new name when they
are installed.
Signed-off-by: Stephen Gallagher <sgallagh@redhat.com>