Refactoring result codes (#731)

* refactoring result codes

- Add a main enum who can handle some orphalin result codes and the default `ResultCode.Success` one.
- Add sub-enum by services when it's needed.
- Remove some empty line.
- Recast all service calls to ResultCode.
- Remove some unneeded static declaration.
- Delete unused `NvHelper` class.

* NvResult is back

* Fix

Ryujinx.HLE/HOS/Services/Lm/ILogger.cs

@@ -10,7 +10,7 @@ namespace Ryujinx.HLE.HOS.Services.Lm
 
         [Command(0)]
         // Log(buffer<unknown, 0x21>)
-        public long Log(ServiceCtx context)
+        public ResultCode Log(ServiceCtx context)
         {
             (long bufPos, long bufSize) = context.Request.GetBufferType0x21();
             byte[] logBuffer = context.Memory.ReadBytes(bufPos, bufSize);
@@ -80,7 +80,7 @@ namespace Ryujinx.HLE.HOS.Services.Lm
                 Logger.PrintGuest(LogClass.ServiceLm, text);
             }
 
-            return 0;
+            return ResultCode.Success;
         }
     }
 }