Bug in EvalRisc5

[dibyendumajumdar]

Codex found this bug

    public void st8(int x, long val) { st4(x,(int)val); st2(x+4,(int)(val>>32)); }

this should be

 public void st8(int x, long val) { st4(x,(int)val); st4(x+4,(int)(val>>32)); }

@Hels15