posix: Hide POSIX_API_Control by default

Update #2514.

cpukit/include/rtems/posix/pthreadimpl.h

@@ -48,6 +48,7 @@ extern "C" {
  */
 extern Thread_Information _POSIX_Threads_Information;
 
+#if defined(RTEMS_POSIX_API)
 RTEMS_INLINE_ROUTINE void _POSIX_Threads_Sporadic_timer_insert(
   Thread_Control    *the_thread,
   POSIX_API_Control *api
@@ -62,6 +63,7 @@ RTEMS_INLINE_ROUTINE void _POSIX_Threads_Sporadic_timer_insert(
     _Timespec_To_ticks( &api->Sporadic.sched_ss_repl_period )
   );
 }
+#endif
 
 void _POSIX_Threads_Sporadic_timer( Watchdog_Control *watchdog );
 

cpukit/include/rtems/posix/threadsup.h

@@ -35,6 +35,7 @@
 extern "C" {
 #endif
 
+#if defined(RTEMS_POSIX_API)
 /**
  * This defines the POSIX API support structure associated with
  * each thread in a system with POSIX configured.
@@ -87,6 +88,7 @@ typedef struct {
    */
   Thread_Action           Signal_action;
 } POSIX_API_Control;
+#endif
 
 /** @} */