Rover: remove unused mavlink_delay(uint32_t ms)

APMrover2/Rover.h

@@ -442,7 +442,6 @@ private:
 
     // compat.cpp
     void delay(uint32_t ms);
-    void mavlink_delay(uint32_t ms);
 
     // control_modes.cpp
     Mode *control_mode_from_num(enum mode num);

APMrover2/compat.cpp

@@ -4,8 +4,3 @@ void Rover::delay(uint32_t ms)
 {
     hal.scheduler->delay(ms);
 }
-
-void Rover::mavlink_delay(uint32_t ms)
-{
-    hal.scheduler->delay(ms);
-}