ArduPlane: remove ability to use DCM as AHRS

ArduPlane/Log.cpp

@@ -35,10 +35,9 @@ void Plane::Log_Write_Attitude(void)
     logger.Write_PID(LOG_PIDY_MSG, yawController.get_pid_info());
     logger.Write_PID(LOG_PIDS_MSG, steerController.get_pid_info());
 
-#if AP_AHRS_NAVEKF_AVAILABLE
     AP::ahrs_navekf().Log_Write();
     ahrs.Write_AHRS2();
-#endif
+
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
     sitl.Log_Write_SIMSTATE();
 #endif

ArduPlane/Parameters.cpp

@@ -979,7 +979,6 @@ const AP_Param::Info Plane::var_info[] = {
     GOBJECT(fence, "FENCE_",        AC_Fence),
 #endif
 
-#if AP_AHRS_NAVEKF_AVAILABLE
 #if HAL_NAVEKF2_AVAILABLE
     // @Group: EK2_
     // @Path: ../libraries/AP_NavEKF2/AP_NavEKF2.cpp
@@ -990,7 +989,6 @@ const AP_Param::Info Plane::var_info[] = {
     // @Group: EK3_
     // @Path: ../libraries/AP_NavEKF3/AP_NavEKF3.cpp
     GOBJECTN(ahrs.EKF3, NavEKF3, "EK3_", NavEKF3),
-#endif
 #endif
 
     // @Group: RPM

ArduPlane/config.h

@@ -38,11 +38,7 @@
 //
 
 #ifndef OPTFLOW
-#if AP_AHRS_NAVEKF_AVAILABLE
  # define OPTFLOW ENABLED
-#else
- # define OPTFLOW DISABLED
-#endif
 #endif