Add C API status constants in tf_status.h

[linuxbckp]

octave_value OCT_TF_OK (void); octave_value OCT_TF_CANCELLED (void); octave_value OCT_TF_UNKNOWN (void); octave_value OCT_TF_INVALID_ARGUMENT (void); octave_value OCT_TF_DEADLINE_EXCEEDED (void); octave_value OCT_TF_NOT_FOUND (void); octave_value OCT_TF_ALREADY_EXISTS (void); octave_value OCT_TF_PERMISSION_DENIED (void); octave_value OCT_TF_UNAUTHENTICATED (void); octave_value OCT_TF_RESOURCE_EXHAUSTED (void); octave_value OCT_TF_FAILED_PRECONDITION (void); octave_value OCT_TF_ABORTED (void); octave_value OCT_TF_OUT_OF_RANGE (void); octave_value OCT_TF_UNIMPLEMENTED (void); octave_value OCT_TF_INTERNAL (void); octave_value OCT_TF_UNAVAILABLE (void); octave_value OCT_TF_DATA_LOSS (void);

[pr0m1th3as]

Hi thanks for your interest working on tensorflow. The TF_Status codes are an enumeration, they can be retrieved already as uint32 values. It is not a good idea to add new C API calls for status codes, hence I will not accept this PR.