1.0.12.5: WITH-ARRAY-DATA touchups

1.0.12.5: WITH-ARRAY-DATA touchups

* Eliminate some double-bounds checks: since WITH-ARRAY-DATA does
  bounds checking, there is no need to vet START and END with
  %CHECK-VECTOR-SEQUENCE-BOUNDS.

* Eliminate some fill-pointer confusion: Since WITH-ARRAY-DATA is
  used both in contexts where fill-pointer needs to be used, and
  in contexts where we only care about the total array size, add
  a :CHECK-FILL-POINTER argument to WITH-ARRAY-DATA.

* Do bounds checking in WITH-ARRAY-DATA based on
  INSERT-ARRAY-BOUNDS-CHECKS policy -- not SPEED vs. SAFETY
  comparison. Adjust tests to check for this.