rtems: rtems_clock_get_ticks_per_second()

Add macro implementation for rtems_clock_get_ticks_per_second() for
C/C++ to avoid the function call overhead.  A
rtems_clock_get_ticks_per_second() is still provided for language
bindings (e.g. Ada).

cpukit/rtems/include/rtems/rtems/clock.h

@@ -198,6 +198,9 @@ RTEMS_INLINE_ROUTINE bool rtems_clock_tick_before(
  */
 rtems_interval rtems_clock_get_ticks_per_second(void);
 
+/* Optimized variant for C/C++ without function call overhead */
+#define rtems_clock_get_ticks_per_second() ( _Watchdog_Ticks_per_second )
+
 /**
  * @brief Set the Current TOD
  *

cpukit/rtems/src/clockgettickspersecond.c

@@ -20,6 +20,8 @@
 
 #include <rtems/rtems/clock.h>
 
+#undef rtems_clock_get_ticks_per_second
+
 rtems_interval rtems_clock_get_ticks_per_second(void)
 {
   return _Watchdog_Ticks_per_second;

testsuites/sptests/spwatchdog/init.c

@@ -62,6 +62,9 @@ static void test_watchdog_config( void )
   rtems_test_assert( _Watchdog_Nanoseconds_per_tick == 10000000 );
   rtems_test_assert( _Watchdog_Ticks_per_second == 100 );
   rtems_test_assert( _Watchdog_Monotonic_max_seconds == 184467440737095516 );
+  rtems_test_assert( rtems_clock_get_ticks_per_second() == 100 );
+  #undef rtems_clock_get_ticks_per_second
+  rtems_test_assert( rtems_clock_get_ticks_per_second() == 100 );
 }
 
 static bool test_watchdog_is_inactive( test_watchdog *watchdog )