Integrate new version of Tensorflow Lite Micro

[mbanth]

We have a improved version of Tensorflow Lite Micro. The developer wants to make it available for use in fwk_voice and specifically the Voice-Noise Ratio component. This issue exists to identify and complete any necessary work to integrate this new version of TFLM.

[uvvpavel]

• Build lib_vnr as a static library
• Use new tflite_mirco_compiler and change vnr calls
• Move calc_vnr_pred into IC
• vnr cleanup
• full xcore build
• full x86 build
• Document ic_calc_vnr_pred
• make sure Windows build works
• All tests passing

[uvvpavel]

One of the python cffi tests exits with the segmentation error which is usually related to using memory outside of the allocated stack or stack running out of memory. This line appears to break the test.
https://github.com/uvvpavel/sw_avona-1/blob/latest_tflite_micro/modules/lib_vnr/src/inference/model/outFile.cpp#L35
Making the kTensorArenaSize larger makes the test pass. This issue will be parked till @panickal-xmos is back from holiday.