core: timer - relocate er_clock_gettime() in cdp module

- benchmark may need it as well

ser_time.h

@@ -37,7 +37,4 @@ time_t ser_time(time_t* t);
  * WARNING: ignores tz (it's obsolete anyway) */
 int ser_gettimeofday(struct timeval* tv, const struct timezone *tz);
 
-/* portable implementation for clock_gettime(CLOCK_REALTIME, ts) */
-int ser_clock_gettime(struct timespec *ts);
-
 #endif /* _ser_time_h */

timer.c

@@ -38,11 +38,6 @@
 #include "error.h"
 #include "signals.h"
 
-#ifdef __OS_darwin
-#include <mach/clock.h>
-#include <mach/mach.h>
-#endif
-
 /*
 #include "config.h"
 */
@@ -1159,22 +1154,4 @@ void slow_timer_main()
 
 }
 
-int ser_clock_gettime(struct timespec *ts)
-{
-#ifdef __OS_darwin
-	clock_serv_t cclock;
-	mach_timespec_t mts;
-
-	/* OS X does not have clock_gettime, use clock_get_time */
-	host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
-	clock_get_time(cclock, &mts);
-	mach_port_deallocate(mach_task_self(), cclock);
-	ts->tv_sec = mts.tv_sec;
-	ts->tv_nsec = mts.tv_nsec;
-	return 0;
-#else
-	return clock_gettime(CLOCK_REALTIME, ts);
-#endif
-}
-
 #endif