Use standard bool type, instead of non-standard boolean_t

sys/kern/subr_bus.c

@@ -584,7 +584,7 @@ filt_devctl_read(struct knote *kn, long hint)
 /**
  * @brief Return whether the userland process is running
  */
-boolean_t
+bool
 devctl_process_running(void)
 {
 	return (devsoftc.inuse == 1);

sys/sys/devctl.h

@@ -35,7 +35,7 @@
  * devctl hooks.  Typically one should use the devctl_notify
  * hook to send the message.
  */
-boolean_t devctl_process_running(void);
+bool devctl_process_running(void);
 void devctl_notify(const char *__system, const char *__subsystem,
     const char *__type, const char *__data);
 struct sbuf;