fix overwriting dedicated_info_nas in connection_request_proc

this fixes an issue in the step() function of the connection_request_proc
in which the dedicated_info_nas message was passed to RRC without
checking if its actually valid or not, i.e. contains a message at all.

because this check was missing and the step() function could be called
multiple-times, the function would overwrite the dedicated_info_nas
in RRC, and therefore causing the connection setup complete to fail

srsue/src/stack/rrc/rrc_procedures.cc

@@ -640,13 +640,20 @@ proc_outcome_t rrc::connection_request_proc::step()
     // Send connectionRequest message to lower layers
     rrc_ptr->send_con_request(cause);
 
-    // Save dedicatedInfoNAS SDU
+    // Save dedicatedInfoNAS SDU, if needed
+    if (dedicated_info_nas.get()) {
       if (rrc_ptr->dedicated_info_nas.get()) {
-      log_h->warning("Received a new dedicatedInfoNAS SDU but there was one still in queue. Removing it.\n");
+        Warning("Received a new dedicatedInfoNAS SDU but there was one still in queue. Removing it.\n");
+        rrc_ptr->dedicated_info_nas.reset();
       }
 
-    Info("Waiting for RRCConnectionSetup/Reject or expiry\n");
+      Debug("Updating dedicatedInfoNAS in RRC\n");
       rrc_ptr->dedicated_info_nas = std::move(dedicated_info_nas);
+    } else {
+      Debug("dedicatedInfoNAS has already been provided to RRC.\n");
+    }
+
+    Info("Waiting for RRCConnectionSetup/Reject or expiry\n");
     state                       = state_t::wait_t300;
     return step();