pager.c: flagging pointer args non vs non-null

Yesterday I said that I'd done all of pager.c and part of objnam.c,
but I was talking about the prototypes in extern.h.  This does more
of the same, this time for the local prototypes in pager.c so "all of
pager.c" should be accurate now.

include/tradstdc.h

@@ -439,7 +439,7 @@ typedef genericptr genericptr_t; /* (void *) or (char *) */
 #define NONNULLS_DEFINED
 #endif  /* NONNULLS_DEFINED */
 #ifndef NO_NNARGS
-#define NO_NNARGS
+#define NO_NNARGS /*empty*/
 #endif  /* NO_NNARGS */
 
 /*