kern: improve KSynchronizationObject, kill KSynchronization

mesosphere/kernel/source/kern_kernel_instantiations.cpp

@@ -26,7 +26,6 @@ namespace ams::kern {
     constinit KMemoryBlockSlabManager Kernel::s_sys_memory_block_manager;
     constinit KBlockInfoManager       Kernel::s_block_info_manager;
     constinit KSupervisorPageTable    Kernel::s_supervisor_page_table;
-    constinit KSynchronization        Kernel::s_synchronization;
     constinit KUnsafeMemory           Kernel::s_unsafe_memory;
     constinit KWorkerTaskManager      Kernel::s_worker_task_managers[KWorkerTaskManager::WorkerType_Count];
     constinit KInterruptManager       Kernel::s_interrupt_manager;