savevm: Remove all the unneeded version_minimum_id_old (usb)

savevm: Remove all the unneeded version_minimum_id_old (usb)

After previous Peter patch, they are redundant.  This way we don't
assign them except when needed.  Once there, there were lots of case
where the ".fields" indentation was wrong:

     .fields = (VMStateField []) {
and
     .fields =      (VMStateField []) {

Change all the combinations to:

     .fields = (VMStateField[]){

The biggest problem (appart from aesthetics) was that checkpatch complained
when we copy&pasted the code from one place to another.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>