Simplify tracking

source/imu.cpp

@@ -34,9 +34,7 @@ void calibrateGyroBias() {
   biasGY = (float)(sy/BIAS_SAMPLES);
   biasGZ = (float)(sz/BIAS_SAMPLES);
   calTempC = readIMUTemp();
-  angleX = angleY = accumX = accumY = 0.0f;
-  // Seed gravity estimate from current accel so projection is correct immediately
-  gravX = imu.readFloatAccelX(); gravY = imu.readFloatAccelY(); gravZ = imu.readFloatAccelZ();
+  accumX = accumY = 0.0f;
 
   #ifdef FEATURE_TELEMETRY
     statRecalCount++;