This implement GetIndirectLayerImageRequiredMemoryInfo call from vi service, accordingly to RE.
Thanks to Thog and gdkchan for helping me to understand some GPU things.
Close#942
* 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