Symbol based PDCCH processing

1. 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.
2. Modify DCI functions to decode DCI in the last PDCCH symbol and
   inidcate to MAC once.
3. Fix PDCCH monitoring for start symbol > 0.
4. Fix multiple PDCCH monitoring within slot.

Co-authored-by: Sakthivel Velumani <mail@sakthi.me>

openair1/SIMULATION/NR_PHY/pbchsim.c

@@ -110,17 +110,6 @@ void nr_fill_rx_indication(fapi_nr_rx_indication_t *rx_ind,
 {
 }
 
-int nr_ue_pdcch_procedures(PHY_VARS_NR_UE *ue,
-                           const UE_nr_rxtx_proc_t *proc,
-                           int32_t pdcch_est_size,
-                           c16_t pdcch_dl_ch_estimates[][pdcch_est_size],
-                           nr_phy_data_t *phy_data,
-                           int n_ss,
-                           c16_t rxdataF[][ue->frame_parms.samples_per_slot_wCP])
-{
-  return 0;
-}
-
 configmodule_interface_t *uniqCfg = NULL;
 int main(int argc, char **argv)
 {