A few RDPs can have 2 GHz + 6 GHz + Scan radio (2 GHz + 5 GHz + 6 GHz)
radios. In this case, the total number of channels are greater than
NUM_CHANNELS.
Hence, increase the channel array size by twice. And filter out the
duplicate channels before sending the channel list to LOWI application.
Change-Id: If9d1676dab24b8e46f5303d5992aaa59ba1e67ce
CRs-Fixed: 3554676