score: Merge tod implementation into one file

Delete TOD_MICROSECONDS_PER_SECOND, TOD_MICROSECONDS_TO_TICKS() and
TOD_MILLISECONDS_TO_TICKS().

testsuites/psxtests/psx01/init.c

@@ -18,6 +18,8 @@
 #include "system.h"
 #include "pritime.h"
 
+#include <rtems/score/tod.h>
+
 void *POSIX_Init(
   void *argument
 )

testsuites/psxtests/psx05/init.c

@@ -17,6 +17,8 @@
 #include "system.h"
 #include <errno.h>
 
+#include <rtems/score/tod.h>
+
 #define MUTEX_BAD_ID 0xfffffffe
 
 void Print_mutexattr(

testsuites/psxtests/psxclock/init.c

@@ -17,6 +17,8 @@
 #include "pmacros.h"
 #include "pritime.h"
 
+#include <rtems/score/tod.h>
+
 /* forward declarations to avoid warnings */
 rtems_task Init(rtems_task_argument argument);
 void check_enosys(int status);