HAL_PX4: minor cleanups

libraries/AP_HAL_PX4/RCInput.cpp

@@ -12,10 +12,7 @@ extern uint16_t ppm_buffer[];
 extern unsigned ppm_decoded_channels;
 extern uint64_t ppm_last_valid_decode;
 
-PX4RCInput::PX4RCInput()
-{}
-
-void PX4RCInput::init(void* machtnichts)
+void PX4RCInput::init(void* unused)
 {
 	clear_overrides();
 }

libraries/AP_HAL_PX4/RCInput.h

@@ -8,7 +8,6 @@
 
 class PX4::PX4RCInput : public AP_HAL::RCInput {
 public:
-    PX4RCInput();
     void init(void* machtnichts);
     uint8_t  valid();
     uint16_t read(uint8_t ch);