Core/Misc: Fix some static analysis issues

Fix some static analysis issues about uninitialized values. Most of them are false positives, always initialized before being accessed, while some of them are real issues spotted by valgrind too.

src/server/game/Movement/MovementGenerators/ConfusedMovementGenerator.h

@@ -26,7 +26,7 @@ template<class T>
 class ConfusedMovementGenerator : public MovementGeneratorMedium< T, ConfusedMovementGenerator<T> >
 {
     public:
-        explicit ConfusedMovementGenerator() : i_nextMoveTime(0) { }
+        explicit ConfusedMovementGenerator() : i_nextMoveTime(0), i_x(0), i_y(0), i_z(0) { }
 
         void DoInitialize(T*);
         void DoFinalize(T*);

src/server/game/Movement/MovementGenerators/RandomMovementGenerator.h

@@ -37,7 +37,6 @@ class RandomMovementGenerator : public MovementGeneratorMedium< T, RandomMovemen
     private:
         TimeTrackerSmall i_nextMoveTime;
 
-        uint32 i_nextMove;
         float wander_distance;
 };
 #endif

src/server/game/Movement/MovementGenerators/WaypointMovementGenerator.h

@@ -117,6 +117,10 @@ class FlightPathMovementGenerator : public MovementGeneratorMedium< Player, Flig
         {
             i_path = &pathnodes;
             i_currentNode = startNode;
+            _endGridX = 0.0f;
+            _endGridY = 0.0f;
+            _endMapId = 0;
+            _preloadTargetNode = 0;
         }
         void DoInitialize(Player*);
         void DoReset(Player*);