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/Apm/PerformanceConfiguration.cs

@@ -15,4 +15,4 @@
         PerformanceConfiguration11 = 0x92220007,
         PerformanceConfiguration12 = 0x92220008
     }
-}
+}