log-view.el calls non-existent function vc-version-diff

[Chris Moore]

The only 2 references to vc-version-diff in the whole lisp/ tree are:

./log-view.el:(autoload 'vc-version-diff "vc")
./log-view.el:    (vc-version-diff (log-view-current-file) to fr)))

So generating a log of a controlled file ("C-x v l") and asking for a
diff ("d") errors:

Debugger entered--Lisp error: (error "Autoloading failed to define
function vc-version-diff")
  vc-version-diff("/home/chris/programs/emacs/lisp/log-view.el" "1.45" "1.46")
  log-view-diff(2537 2537)