* move external to interface

tests/tbs/ub0170.pp

@@ -5,7 +5,7 @@ unit ub0170;
 
 interface
 
-   procedure a;
+   procedure a;external name '_assembler_a';
    procedure c;
 
    const is_called : boolean = false;
@@ -23,7 +23,5 @@ implementation
         Is_called:=true;
      end;
 
-   procedure a;external name '_assembler_a';
-
 end.