Refactor SVC handler (#540)

* Refactor SVC handler

* Get rid of KernelErr

* Split kernel code files into multiple folders

Ryujinx.HLE/HOS/Kernel/Memory/MemoryOperation.cs

@@ -0,0 +1,12 @@
+namespace Ryujinx.HLE.HOS.Kernel.Memory
+{
+    enum MemoryOperation
+    {
+        MapPa,
+        MapVa,
+        Allocate,
+        Unmap,
+        ChangePermRw,
+        ChangePermsAndAttributes
+    }
+}