Move RunThread to architecture-specific implementations

xtoskrnl/ke/amd64/kthread.cc

@@ -137,3 +137,16 @@ KE::KThread::InitializeThreadContext(IN PKTHREAD Thread,
     Thread->InitialStack = (PVOID)&ThreadFrame->NpxFrame;
     Thread->KernelStack = &ThreadFrame->SwitchFrame;
 }
+
+/**
+ * Serves as the initial execution point for all threads after first context switch.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+KE::KThread::RunThread(VOID)
+{
+}