Address integrity failure after UE reconnects from RRC IDLE

After a new connection from RRC IDLE, an integrity failure occurs. This
commit is addressing this issue to pass the integrity check.

* Reset ciphering and integrity algorithms when going into RRC IDLE

* Use uplink NAS COUNT in Registration Request for initial KgNB derivation
  * Temporarily deriving UP protection keys in Registration Request
  * Note: AS SMC handling should be done according to 33.501 §6.8.1.1.2.2

openair2/RRC/NR_UE/rrc_UE.c

@@ -2562,6 +2562,8 @@ void nr_rrc_going_to_IDLE(NR_UE_RRC_INST_t *rrc,
 
   // discard the keys (only kgnb is stored)
   memset(rrc->kgnb, 0, sizeof(rrc->kgnb));
+  rrc->integrityProtAlgorithm = 0;
+  rrc->cipheringAlgorithm = 0;
 
   // release all radio resources, including release of the RLC entity,
   // the MAC configuration and the associated PDCP entity