Kernel: Store SchedulerThreadNode directly in Thread

Having the pointer indirection was weird and forced allocations when
adding/binding a new thread :P

kernel/kernel/ThreadBlocker.cpp

@@ -37,7 +37,7 @@ namespace Kernel
 			node->block_chain_prev = nullptr;
 			node->block_chain_next = nullptr;
 
-			Processor::scheduler().unblock_thread(node);
+			Processor::scheduler().unblock_thread(node->thread);
 
 			node = next;
 		}