Previously it was only checking `salt-key -l pre` in the while loop. If you reboot the VM after the key is accepted, then then the reboot will fail as it was only checking `pre` and not `acc`.  

This change has it check `salt-key -l acc` first under the same rules as `salt-key -l pre` (line count greater than 1). 

It performs this `acc` check outside of the while loop, setting the `key_staged` value accordingly.

If the key has already been accepted it `key_staged` will be true, and the while loop will be skipped continuing the load process as the key has been accepted.