Fix a braino in CL:FINISH-OUTPUT which called ecl_force_output

The function CL:FINISH-OUTPUT called by accident ECL_FORCE_OUTPUT when used on
ANSI streams. That becames an issue when we call it on a two-way stream where
the output buffer was a gray stream with STREAM-FINISH-OUTPUT differing from
STREAM-FORCE-OUTPUT.

src/c/print.d

@@ -283,7 +283,7 @@ ecl_print_circle(void)
     return _ecl_funcall2(@'gray::stream-finish-output', strm);
   }
 #endif
-  ecl_force_output(strm);
+  ecl_finish_output(strm);
   @(return ECL_NIL);
   @)