SETF of an array

[Guy.Steele at CMU-10A]

I sympathize somewhat with GJC's complaint, but note that if instead of ARRAY
you use *ARRAY (or (ARRAY NIL ...)) to create a true array object instead
of a named array, then (SETF (ARRAYCALL ...) ...) is easily made to work
(I think SETF does already work for this case?).