Refactor SVC handler (#540)

* Refactor SVC handler

* Get rid of KernelErr

* Split kernel code files into multiple folders

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

@@ -0,0 +1,22 @@
+using System;
+
+namespace Ryujinx.HLE.HOS.Kernel.Memory
+{
+    [Flags]
+    enum MemoryAttribute  : byte
+    {
+        None = 0,
+        Mask = 0xff,
+
+        Borrowed     = 1 << 0,
+        IpcMapped    = 1 << 1,
+        DeviceMapped = 1 << 2,
+        Uncached     = 1 << 3,
+
+        IpcAndDeviceMapped = IpcMapped | DeviceMapped,
+
+        BorrowedAndIpcMapped = Borrowed | IpcMapped,
+
+        DeviceMappedAndUncached = DeviceMapped | Uncached
+    }
+}