boards: simplify RC port configuration by using NuttX ioctl's

A board only needs to define:
 #define RC_SERIAL_PORT                     "/dev/ttyS4"

Then it can optionally define one or more of the following:
 #define RC_SERIAL_SWAP_RXTX
 #define RC_SERIAL_SINGLEWIRE
 #define RC_INVERT_INPUT(_invert_true) px4_arch_gpiowrite(GPIO_SBUS_INV, _invert_true)

src/drivers/rc_input/RCInput.hpp

@@ -63,7 +63,7 @@ class RCInput : public ModuleBase<RCInput>
 {
 public:
 
-	RCInput(bool run_as_task);
+	RCInput(bool run_as_task, char *device);
 	virtual ~RCInput();
 
 	/** @see ModuleBase */
@@ -132,6 +132,7 @@ private:
 	orb_advert_t	_to_input_rc{nullptr};
 
 	int		_rcs_fd{-1};
+	char		_device[20] {};					///< device / serial port path
 
 	uint8_t _rcs_buf[SBUS_BUFFER_SIZE] {};
 
@@ -144,6 +145,7 @@ private:
 	perf_counter_t      _publish_interval_perf;
 
 	static void	cycle_trampoline(void *arg);
+	static void	cycle_trampoline_init(void *arg);
 	int 		start();
 
 	void fill_rc_in(uint16_t raw_rc_count_local,
@@ -153,6 +155,6 @@ private:
 
 	void set_rc_scan_state(RC_SCAN _rc_scan_state);
 
-	void rc_io_invert(bool invert, uint32_t uxart_base);
+	void rc_io_invert(bool invert);
 
 };