AP_NavEKF3: move badMagYaw onto stack

libraries/AP_NavEKF3/AP_NavEKF3_MagFusion.cpp

@@ -145,7 +145,7 @@ void NavEKF3_core::realignYawGPS()
         float yawErr = MAX(fabsf(wrap_PI(gpsYaw - velYaw)),fabsf(wrap_PI(gpsYaw - eulerAngles.z)));
 
         // If the angles disagree by more than 45 degrees and GPS innovations are large or no previous yaw alignment, we declare the magnetic yaw as bad
-        badMagYaw = ((yawErr > 0.7854f) && (velTestRatio > 1.0f) && (PV_AidingMode == AID_ABSOLUTE)) || !yawAlignComplete;
+        bool badMagYaw = ((yawErr > 0.7854f) && (velTestRatio > 1.0f) && (PV_AidingMode == AID_ABSOLUTE)) || !yawAlignComplete;
 
         // correct yaw angle using GPS ground course if compass yaw bad
         if (badMagYaw) {

libraries/AP_NavEKF3/AP_NavEKF3_core.cpp

@@ -429,7 +429,6 @@ void NavEKF3_core::InitialiseVariablesMag()
     magYawResetTimer_ms = imuSampleTime_ms;
     magTimeout = false;
     allMagSensorsFailed = false;
-    badMagYaw = false;
     finalInflightMagInit = false;
     mag_state.q0 = 1;
     mag_state.DCM.identity();

libraries/AP_NavEKF3/AP_NavEKF3_core.h

@@ -943,7 +943,6 @@ private:
     bool hgtTimeout;                // boolean true if height measurements have failed innovation consistency check and timed out
     bool magTimeout;                // boolean true if magnetometer measurements have failed for too long and have timed out
     bool tasTimeout;                // boolean true if true airspeed measurements have failed for too long and have timed out
-    bool badMagYaw;                 // boolean true if the magnetometer is declared to be producing bad data
     bool badIMUdata;                // boolean true if the bad IMU data is detected
 
     float gpsNoiseScaler;           // Used to scale the  GPS measurement noise and consistency gates to compensate for operation with small satellite counts