Move uORB Subscription getter to header file (#6891)

src/modules/uORB/Subscription.cpp

@@ -151,9 +151,6 @@ bool Subscription<T>::check_updated()
 	return SubscriptionBase::updated();
 }
 
-template <class T>
-const T &Subscription<T>::get() { return _data; }
-
 template class __EXPORT Subscription<actuator_armed_s>;
 template class __EXPORT Subscription<actuator_controls_s>;
 template class __EXPORT Subscription<att_pos_mocap_s>;

src/modules/uORB/Subscription.hpp

@@ -193,7 +193,7 @@ public:
 	/*
 	 * This function gets the T struct data
 	 * */
-	const T &get();
+	const T &get() const { return _data; }
 private:
 	T _data;
 };