global: use static method to construct AC_Fence

ArduCopter/Copter.cpp

@@ -66,9 +66,6 @@ Copter::Copter(void)
     mainLoop_count(0),
     rtl_loiter_start_time(0),
     auto_trim_counter(0),
-#if AC_FENCE == ENABLED
-    fence(ahrs, inertial_nav),
-#endif
 #if AC_AVOID_ENABLED == ENABLED
     avoid(ahrs, inertial_nav, fence, g2.proximity, &g2.beacon),
 #endif

ArduCopter/Copter.h

@@ -554,8 +554,9 @@ private:
 
     // AC_Fence library to reduce fly-aways
 #if AC_FENCE == ENABLED
-    AC_Fence    fence;
+    AC_Fence fence = AC_Fence::create(ahrs, inertial_nav);
 #endif
+
 #if AC_AVOID_ENABLED == ENABLED
     AC_Avoid avoid;
 #endif

ArduSub/Sub.cpp

@@ -59,9 +59,6 @@ Sub::Sub(void)
           pmTest1(0),
           fast_loopTimer(0),
           mainLoop_count(0),
-#if AC_FENCE == ENABLED
-          fence(ahrs, inertial_nav),
-#endif
 #if AC_RALLY == ENABLED
           rally(ahrs),
 #endif

ArduSub/Sub.h

@@ -426,7 +426,7 @@ private:
 
     // AC_Fence library to reduce fly-aways
 #if AC_FENCE == ENABLED
-    AC_Fence    fence;
+    AC_Fence fence = AC_Fence::create(ahrs, inertial_nav);
 #endif
 
     // Rally library