NvServices refactoring (#120)

* Initial implementation of NvMap/NvHostCtrl

* More work on NvHostCtrl

* Refactoring of nvservices, move GPU Vmm, make Vmm per-process, refactor most gpu devices, move Gpu to Core, fix CbBind

* Implement GetGpuTime, support CancelSynchronization, fix issue on InsertWaitingMutex, proper double buffering support (again, not working properly for commercial games, only hb)

* Try to fix perf regression reading/writing textures, moved syncpts and events to a UserCtx class, delete global state when the process exits, other minor tweaks

* Remove now unused code, add comment about probably wrong result codes

Ryujinx.Core/Gpu/TextureHelper.cs

@@ -0,0 +1,36 @@
+using ChocolArm64.Memory;
+using System;
+
+namespace Ryujinx.Core.Gpu
+{
+    static class TextureHelper
+    {
+        public static ISwizzle GetSwizzle(Texture Texture, int Width, int Bpp)
+        {
+            switch (Texture.Swizzle)
+            {
+                case TextureSwizzle.Pitch:
+                case TextureSwizzle.PitchColorKey:
+                     return new LinearSwizzle(Texture.Pitch, Bpp);
+
+                case TextureSwizzle.BlockLinear:
+                case TextureSwizzle.BlockLinearColorKey:
+                    return new BlockLinearSwizzle(Width, Bpp, Texture.BlockHeight);
+            }
+
+            throw new NotImplementedException(Texture.Swizzle.ToString());
+        }
+
+        public static (AMemory Memory, long Position) GetMemoryAndPosition(
+            IAMemory Memory,
+            long     Position)
+        {
+            if (Memory is NvGpuVmm Vmm)
+            {
+                return (Vmm.Memory, Vmm.GetPhysicalAddress(Position));
+            }
+
+            return ((AMemory)Memory, Position);
+        }
+    }
+}