Core/Units: make use of the PlayHoverAnim update flag to store the play hover anim state

* this fixes playing hover animations for units which have enabled their hover animation without using anim tiers

src/server/game/Entities/Unit/Unit.cpp

@@ -378,7 +378,6 @@ Unit::Unit(bool isWorldObject) :
 
     _oldFactionId = 0;
     _isWalkingBeforeCharm = false;
-    _playHoverAnim = false;
 }
 
 ////////////////////////////////////////////////////////////
@@ -13636,7 +13635,7 @@ void Unit::SetPlayHoverAnim(bool enable, bool sendUpdate /*= true*/)
     if (IsPlayingHoverAnim() == enable)
         return;
 
-    _playHoverAnim = enable;
+    m_updateFlag.PlayerHoverAnim = enable;
 
     if (!sendUpdate)
         return;

src/server/game/Entities/Unit/Unit.h

@@ -1043,7 +1043,7 @@ class TC_GAME_API Unit : public WorldObject
 
         void MonsterMoveWithSpeed(float x, float y, float z, float speed, bool generatePath = false, bool forceDestination = false);
 
-        bool IsPlayingHoverAnim() const { return _playHoverAnim; }
+        bool IsPlayingHoverAnim() const { return m_updateFlag.PlayerHoverAnim; }
         void SetPlayHoverAnim(bool enable, bool sendUpdate = true);
 
         bool IsGravityDisabled() const { return m_movementInfo.HasMovementFlag(MOVEMENTFLAG_DISABLE_GRAVITY); }
@@ -1792,8 +1792,6 @@ class TC_GAME_API Unit : public WorldObject
         uint32 _oldFactionId;           ///< faction before charm
         bool _isWalkingBeforeCharm;     ///< Are we walking before we were charmed?
 
-        bool _playHoverAnim;
-
         std::unique_ptr<SpellHistory> m_spellHistory;
 
         PositionUpdateInfo _positionUpdateInfo;