Refactor SVC handler (#540)

* Refactor SVC handler

* Get rid of KernelErr

* Split kernel code files into multiple folders

Ryujinx.HLE/HOS/Kernel/Common/IKFutureSchedulerObject.cs

@@ -0,0 +1,7 @@
+namespace Ryujinx.HLE.HOS.Kernel.Common
+{
+    interface IKFutureSchedulerObject
+    {
+        void TimeUp();
+    }
+}