scheduler: pid refcount

kernel-src/sys/syscalls/fork.c

@@ -57,6 +57,8 @@ syscallret_t syscall_fork(context_t *ctx) {
 	ret.ret = nproc->pid;
 
 	sched_queue(nthread);
+	// proc starts with 1 refcount, release it here as to only have the thread reference
+	PROC_RELEASE(nproc);
 
 	cleanup:
 	return ret;

kernel-src/sys/syscalls/waitpid.c

@@ -75,6 +75,7 @@ syscallret_t syscall_waitpid(context_t *context, pid_t pid, int *status, int opt
 	ret.errno = 0;
 
 	__assert(iterator);
-	sched_destroyproc(iterator);
+	// process will no longer be referenced by the child list
+	PROC_RELEASE(iterator);
 	return ret;
 }