AP_Baro: disable BARO_FIELD_ELV for sub

libraries/AP_Baro/AP_Baro.cpp

@@ -74,6 +74,10 @@
 #define HAL_BARO_ALLOW_INIT_NO_BARO
 #endif
 
+#ifndef AP_FIELD_ELEVATION_ENABLED
+#define AP_FIELD_ELEVATION_ENABLED !defined(HAL_BUILD_AP_PERIPH) && !APM_BUILD_TYPE(APM_BUILD_ArduSub)
+#endif
+
 extern const AP_HAL::HAL& hal;
 
 // table of user settable parameters
@@ -219,7 +223,7 @@ const AP_Param::GroupInfo AP_Baro::var_info[] = {
     // @Path: AP_Baro_Wind.cpp
     AP_SUBGROUPINFO(sensors[2].wind_coeff, "3_WCF_", 20, AP_Baro, WindCoeff),
 #endif
-#ifndef HAL_BUILD_AP_PERIPH
+#if AP_FIELD_ELEVATION_ENABLED
     // @Param: _FIELD_ELV
     // @DisplayName: field elevation
     // @Description: User provided field elevation in meters. This is used to improve the calculation of the altitude the vehicle is at. This parameter is not persistent and will be reset to 0 every time the vehicle is rebooted. Changes to this parameter will only be used when disarmed. A value of 0 means the EKF origin height is used for takeoff height above sea level.
@@ -958,7 +962,7 @@ void AP_Baro::update(void)
             }
         }
     }
-#ifndef HAL_BUILD_AP_PERIPH
+#if AP_FIELD_ELEVATION_ENABLED
     update_field_elevation();
 #endif