Avoid invalid typecast from classref (cpointerdef) to class (tx86pointerdef) in n8086mem unit, instead typecast to tx86pointerdefclass

compiler/i8086/n8086mem.pas

@@ -189,7 +189,7 @@ implementation
 
     function ti8086vecnode.get_address_type: tdef;
       begin
-        result:=tx86pointerdef(cpointerdef).getreusablex86(resultdef,x86pt_near);
+        result:=tx86pointerdefclass(cpointerdef).getreusablex86(resultdef,x86pt_near);
       end;
 
 
@@ -219,7 +219,7 @@ implementation
             result:=ccallnode.createintern(procname,
               ccallparanode.create(right,
               ccallparanode.create(ttypeconvnode(left).left,nil)));
-            inserttypeconv_internal(result,tx86pointerdef(cpointerdef).getreusablex86(arraydef.elementdef,x86pt_huge));
+            inserttypeconv_internal(result,tx86pointerdefclass(cpointerdef).getreusablex86(arraydef.elementdef,x86pt_huge));
             result:=cderefnode.create(result);
 
             ttypeconvnode(left).left:=nil;