New input/process plugin to accept IPFIX flow records on a socket

[lokeshdh]

The devices that we use have IPFIX support in the silicon which allows us to identify IPFIX flows. This new plugin allows the IPFIX flow data to be passed onto the IPFIXPROBE's sock(Unix domain socket) plugin which allows the tool to generate IPFIX data packets and export them to the collector.

Additional changes:

• Some bug fixes identified during testing.
• To not increase the device's release file size I have made following support conditional: Making LZ4 conditionally compile via -DENABLE_OUTPUT_LZ4=ON Making UNWIND conditionally compile via -DENABLE_UNWIND=ON

[SiskaPavel]

Hi Lokesh,

sorry for not getting back to your MR earlier. At the moment we are working on major changes in the processing plugins, which will be integrated soon. After that, I will be able to review and merge your MR, potentially adapting it to the new API.

Thanks a lot for your contribution and patience!

Pavel