AP_NavEKF2: remove unused innovationIncrement and lastInnovation

libraries/AP_NavEKF2/AP_NavEKF2_core.cpp

@@ -239,8 +239,6 @@ void NavEKF2_core::InitialiseVariables()
     gpsNotAvailable = true;
     motorsArmed = false;
     prevMotorsArmed = false;
-    innovationIncrement = 0;
-    lastInnovation = 0;
     memset(&gpsCheckStatus, 0, sizeof(gpsCheckStatus));
     gpsSpdAccPass = false;
     ekfInnovationsPass = false;

libraries/AP_NavEKF2/AP_NavEKF2_core.h

@@ -1061,10 +1061,6 @@ private:
     uint32_t lastInnovFailTime_ms;  // last time in msec the GPS innovations failed
     bool gpsAccuracyGood;           // true when the GPS accuracy is considered to be good enough for safe flight.
 
-    // States used for unwrapping of compass yaw error
-    float innovationIncrement;
-    float lastInnovation;
-
     // variables added for optical flow fusion
     obs_ring_buffer_t<of_elements> storedOF;    // OF data buffer
     of_elements ofDataNew;          // OF data at the current time horizon