Introduce BUILD_TFLITE_BENCHMARK_MODEL option (#2226)

Introduce BUILD_TFLITE_BENCHMARK_MODEL option (#2226)

Related Issue: #1760, #1696

`tflite_benchmark_model` is a tool for profiling a given model.
The tools is under development in tensorflow upstream.

It was not shipped in v1.9.0 release.
Thus I made `tflite_benchmark_model` work for tflite interpreter
by chery-picking needed patches. (#2212)

This patch is a part of full changes. It only introduces build option.

By default, tflite_benchmark_model will not be built.

To build tflite_benchmark_model tool, use

```
$ OPTIONS='-DBUILD_PURE_ARM_COMPUTE=ON -DBUILD_TFLITE_BENCHMARK_MODEL=ON' \
CROSS_BUILD=1 TARGET_ARCH=armv7l make all install
```

Signed-off-by: Sanggyu Lee <sg5.lee@samsung.com>