AP_NavEKF3: remove wheel encoder update limit

libraries/AP_NavEKF3/AP_NavEKF3.h

@@ -233,6 +233,7 @@ public:
      * timeStamp_ms is the time when the rotation was last measured (msec)
      * posOffset is the XYZ body frame position of the wheel hub (m)
      * radius is the effective rolling radius of the wheel (m)
+     * this should not be called at more than the EKF's update rate (50hz or 100hz)
     */
     void writeWheelOdom(float delAng, float delTime, uint32_t timeStamp_ms, const Vector3f &posOffset, float radius);
 

libraries/AP_NavEKF3/AP_NavEKF3_Measurements.cpp

@@ -140,9 +140,10 @@ void NavEKF3_core::writeWheelOdom(float delAng, float delTime, uint32_t timeStam
     // It uses the exisiting body frame velocity fusion.
     // TODO implement a dedicated wheel odometry observation model
 
+    // rate limiting to 50hz should be done by the caller
     // limit update rate to maximum allowed by sensor buffers and fusion process
     // don't try to write to buffer until the filter has been initialised
-    if (((timeStamp_ms - wheelOdmMeasTime_ms) < frontend->sensorIntervalMin_ms) || (delTime < dtEkfAvg) || !statesInitialised) {
+    if ((delTime < dtEkfAvg) || !statesInitialised) {
         return;
     }