Copter: add use_pilot_yaw to ModeSmartRTL class

ArduCopter/mode.h

@@ -1266,6 +1266,7 @@ public:
     void exit() override;
 
     bool is_landing() const override;
+    bool use_pilot_yaw() const override;
 
     // Safe RTL states
     enum class SubMode : uint8_t {

ArduCopter/mode_smart_rtl.cpp

@@ -82,7 +82,7 @@ void ModeSmartRTL::wait_cleanup_run()
 void ModeSmartRTL::path_follow_run()
 {
     float target_yaw_rate = 0.0f;
-    if (!copter.failsafe.radio && g2.smart_rtl.use_pilot_yaw()) {
+    if (!copter.failsafe.radio && use_pilot_yaw()) {
         // get pilot's desired yaw rate
         target_yaw_rate = get_pilot_desired_yaw_rate(channel_yaw->get_control_in());
         if (!is_zero(target_yaw_rate)) {
@@ -207,4 +207,9 @@ int32_t ModeSmartRTL::wp_bearing() const
     return wp_nav->get_wp_bearing_to_destination();
 }
 
+bool ModeSmartRTL::use_pilot_yaw() const
+{
+    return g2.smart_rtl.use_pilot_yaw();
+}
+
 #endif