Fix ulprbbl based on SRS

Fix ulprbbl based on SRS, this fix prevents the gNB to compute ulprbbl when it does not detect SRS from the UE. Otherwise all the PRBs become blacklisted in case of a RRCRelease (for example) and gNB will never have resources to schedule PUSCH/PUCCH for other UEs.

openair1/PHY/defs_gNB.h

@@ -840,6 +840,7 @@ typedef struct PHY_VARS_gNB_s {
   int pucch0_thres;
   int pusch_thres;
   int prach_thres;
+  int srs_thres;
   uint64_t bad_pucch;
   int num_ulprbbl;
   int ulprbbl[275];