Fix engine obstruction cluster position typo

Obstruction cluster are found in walls. Since position of walls would never change, that erroneous code path was probably never executed, hence it never caused any observable problems. Fixing this anyway in case it would be relevant in future.

source/simulation2/components/CCmpObstruction.cpp

@@ -367,7 +367,7 @@ public:
 					m_Tag = cmpObstructionManager->AddUnitShape(GetEntityId(),
 						data.x, data.z, m_Clearance, (flags_t)(m_Flags | (m_Moving ? ICmpObstructionManager::FLAG_MOVING : 0)), m_ControlGroup);
 				else
-					AddClusterShapes(data.x, data.x, data.a);
+					AddClusterShapes(data.x, data.z, data.a);
 			}
 			else if (!data.inWorld && m_Tag.valid())
 			{