global: use static method to construct RCMapper

APMrover2/Rover.h

@@ -133,7 +133,7 @@ private:
     AP_Scheduler scheduler = AP_Scheduler::create();
 
     // mapping between input channels
-    RCMapper rcmap;
+    RCMapper rcmap = RCMapper::create();
 
     // board specific config
     AP_BoardConfig BoardConfig;

ArduCopter/Copter.h

@@ -314,7 +314,7 @@ private:
     // altitude below which we do no navigation in auto takeoff
     float auto_takeoff_no_nav_alt_cm;
 
-    RCMapper rcmap;
+    RCMapper rcmap = RCMapper::create();
 
     // board specific config
     AP_BoardConfig BoardConfig;

ArduPlane/Plane.h

@@ -169,7 +169,7 @@ private:
     AP_Scheduler scheduler = AP_Scheduler::create();
 
     // mapping between input channels
-    RCMapper rcmap;
+    RCMapper rcmap = RCMapper::create();
 
     // board specific config
     AP_BoardConfig BoardConfig;

ArduSub/Sub.h

@@ -251,7 +251,7 @@ private:
     mode_reason_t prev_control_mode_reason = MODE_REASON_UNKNOWN;
 
 #if RCMAP_ENABLED == ENABLED
-    RCMapper rcmap;
+    RCMapper rcmap = RCMapper::create();
 #endif
 
     // board specific config