Move comment about calling convention for directionless parameters ou…

…t of list

p4-16/spec/P4-16-spec.mdk

@@ -1506,8 +1506,7 @@ Each parameter may be labeled with a direction:
   - For anything other than an action, e.g. a control, parser, or
     function, a directionless parameter means that the value supplied
     as an argument in a call must be a compile-time known value
-    (see Section [#sec-compile-time-known]). Note that a directionless 
-    parameter of extern object type is passed by reference.
+    (see Section [#sec-compile-time-known]).
   - For an action, a directionless parameter indicates that it is
     "action data".  See Section [#sec-actions] for the meaning of
     action data, but its meaning includes the following possibilities:
@@ -1518,6 +1517,8 @@ Each parameter may be labeled with a direction:
       when an entry is added to a table that uses that action.  See
       Section [#sec-actions].
 
+A directionless parameter of extern object type is passed by reference.
+
 Direction `out` parameters are always initialized at the beginning of
 execution of the portion of the program that has the `out` parameters,
 e.g. `control`, `parser`, `action`, function, etc.  This