SITL: correct RC2_REV to RC2_REVERSED in comment

libraries/SITL/SIM_JSBSim.cpp

@@ -346,7 +346,7 @@ void JSBSim::send_servos(const struct sitl_input &input)
         float ch1 = aileron;
         float ch2 = elevator;
         aileron  = (ch2-ch1)/2.0f;
-        // the minus does away with the need for RC2_REV=-1
+        // the minus does away with the need for RC2_REVERSED=-1
         elevator = -(ch2+ch1)/2.0f;
     } else if (frame == FRAME_VTAIL) {
         // fake a vtail plane

libraries/SITL/SIM_Plane.cpp

@@ -268,7 +268,7 @@ void Plane::calculate_forces(const struct sitl_input &input, Vector3f &rot_accel
         float ch1 = aileron;
         float ch2 = elevator;
         aileron  = (ch2-ch1)/2.0f;
-        // the minus does away with the need for RC2_REV=-1
+        // the minus does away with the need for RC2_REVERSED=-1
         elevator = -(ch2+ch1)/2.0f;
 
         // assume no rudder