[tf2tflite] Schema for additional info of Custom Op from user (#5939)

[tf2tflite] Schema for additional info of Custom Op from user (#5939)

* [tf2tflite] Schema for additional info of Custom Op from user

This is a schema for additional info of Custom Op from user.
It was committed into _moco-tf_ but moved to here.
The name was renamed to CompileInfo.pbtxt (Previous name was Model.MetaInfo.pbtxt), which seems more friendlier. :-)

Signed-off-by: Hyun Sik Yoon <hyunsik.yoon@samsung.com>
* renaming CompileInfo to CustomInfo && move ./proto/CMakeFiles.txt to ./CMakeFiles.txt

* modify DT_INT32 to 15