HAL_VRBRain: fixed functor comparison

libraries/AP_HAL_VRBRAIN/Scheduler.cpp

@@ -219,7 +219,7 @@ void VRBRAINScheduler::_run_timers(bool called_from_timer_thread)
     if (!_timer_suspended) {
         // now call the timer based drivers
         for (int i = 0; i < _num_timer_procs; i++) {
-            if (_timer_proc[i] != NULL) {
+            if (_timer_proc[i]) {
                 _timer_proc[i]();
             }
         }
@@ -228,7 +228,7 @@ void VRBRAINScheduler::_run_timers(bool called_from_timer_thread)
     }
 
     // and the failsafe, if one is setup
-    if (_failsafe != NULL) {
+    if (_failsafe) {
         _failsafe();
     }
 
@@ -279,7 +279,7 @@ void VRBRAINScheduler::_run_io(void)
     if (!_timer_suspended) {
         // now call the IO based drivers
         for (int i = 0; i < _num_io_procs; i++) {
-            if (_io_proc[i] != NULL) {
+            if (_io_proc[i]) {
                 _io_proc[i]();
             }
         }