FPGA: 2 TX DSP was removed. 2 RX DSP was added.
ZPU: 2 TX DSP was removed. 2 RX DSP was added.
HOST: Few acks for the 4xDDC version.
HOST: 2 RX DSP was added.

This commit must be merged with previous.
FPGA: Frontend switch was changed according with 4ddc mode.
HOST: Add file writing capability to rx_multi_samples example.
HOST: Ability to connect signal from lms chip onto several DSP was added.