Refactor PDCCH PHY functions to take rxdataF of one OFDM symbol and
produce LLR for each search space. The modified functions take
rxdataF in a different format than that produced by nr_slot_fep(). So
for now a memcpy is used to change the array structure. Once
nr_slot_fep() is modified, this memcpy will no longer be needed and
will be removed.
Modify DCI functions to decode DCI in the last PDCCH symbol and
inidcate to MAC once.