Posix: fix event_wait_timed() (#346)

event_wait_timed() was ignoring a timeout of 1000 ms.
Presumably this is because pthread_cond_timedwait() only
considers tv_nsec less than one second.

Convert the timeout in miliseconds to second and nanosecond
components to fix this.

Co-authored-by: alfred gedeon <28123637+alfred2g@users.noreply.github.com>

portable/ThirdParty/GCC/Posix/utils/wait_for_event.c

@@ -76,8 +76,8 @@ bool event_wait_timed( struct event * ev,
     int ret = 0;
 
     clock_gettime( CLOCK_REALTIME, &ts );
-    //ts.tv_sec += ms;
+    ts.tv_sec += ms / 1000;
-    ts.tv_nsec += (ms * 1000000);
+    ts.tv_nsec += ((ms % 1000) * 1000000);
     pthread_mutex_lock( &ev->mutex );
 
     while( (ev->event_triggered == false) && (ret == 0) )