Kernel: Don't log profile data before/after the process/thread lifetime

There were a few cases where we could end up logging profiling events
before or after the associated process or thread exists in the profile:

After enabling profiling we might end up with CPU samples before we
had a chance to synthesize process/thread creation events.

After a thread exits we would still log associated kmalloc/kfree
events. Instead we now just ignore those events.

Kernel/Scheduler.cpp

@@ -445,11 +445,6 @@ void Scheduler::prepare_for_idle_loop()
     scheduler_data.m_in_scheduler = true;
 }
 
-bool Scheduler::colonel_initialized()
-{
-    return !!s_colonel_process;
-}
-
 Process* Scheduler::colonel()
 {
     VERIFY(s_colonel_process);