pwm_out_sim: cleanup, avoid unnecessary & incorrect init of _control_subs

These need to be set to -1.

src/drivers/pwm_out_sim/PWMSim.hpp

@@ -31,8 +31,7 @@
  *
  ****************************************************************************/
 
-#ifndef DRIVERS_PWM_OUT_SIM_PWMSIM_HPP_
-#define DRIVERS_PWM_OUT_SIM_PWMSIM_HPP_
+#pragma once
 
 #include <string.h>
 
@@ -104,7 +103,7 @@ private:
 	int 		_update_rate{400};
 	int 		_current_update_rate{0};
 
-	int			_control_subs[actuator_controls_s::NUM_ACTUATOR_CONTROL_GROUPS] {};
+	int			_control_subs[actuator_controls_s::NUM_ACTUATOR_CONTROL_GROUPS];
 
 	px4_pollfd_struct_t	_poll_fds[actuator_controls_s::NUM_ACTUATOR_CONTROL_GROUPS] {};
 	unsigned	_poll_fds_num{0};
@@ -142,4 +141,3 @@ private:
 	void 	update_params();
 };
 
-#endif /* DRIVERS_PWM_OUT_SIM_PWMSIM_HPP_ */