Small frameset bug

[JD Smith]

In `frameset--minibufferless-last-p`, the destructuring statements:

(pcase-let ((`(,hasmini1 ,id-def1) (assq 'frameset--mini (car state1)))
              (`(,hasmini2 ,id-def2) (assq 'frameset--mini (car state2))))

do not function as intended.  Since the `assq` always produces ‘frameset—mini` 
as its car, hasmini1/2 are always set to this symbol. The subsequent `cond` 
still works as intended to sort minibufferless frames last:

    (cond ((eq id-def1 t) t)
          ((eq id-def2 t) nil)
          ((not (eq hasmini1 hasmini2)) (eq hasmini1 t))
          ((eq hasmini1 nil) (or id-def1 id-def2))
          (t t))))

but the 3rd and 4th conditions are never met.  This may cause confusion for 
anyone trying to use the ‘frameset—mini frame parameter.