xrPhysics: fix linkage virtal destructors for xrGame on Windows

Author: eagleivg

src/xrPhysics/IClimableObject.h

@@ -39,5 +39,9 @@ class IClimableObject
     virtual IPhysicsShellHolder* cast_IPhysicsShellHolder() = 0;
 
 protected:
+#if defined(WINDOWS)
+    virtual ~IClimableObject() = 0 {}
+#elif defined(LINUX)
     virtual ~IClimableObject() = 0;
+#endif
 };

src/xrPhysics/icollisiondamagereceiver.h

@@ -13,7 +13,11 @@ class ICollisionDamageReceiver
     virtual void CollisionHit(u16 source_id, u16 bone_id, float power, const Fvector& dir, Fvector& pos) = 0;
 
 protected:
+#if defined(WINDOWS)
+    virtual ~ICollisionDamageReceiver() = 0 {}
+#elif defined(LINUX)
     virtual ~ICollisionDamageReceiver() = 0;
+#endif
 };
 
 struct dContact;