HOTFIX: cherry-picked from b7a027f9

 --> only on the lte side
 fixes for mutex lock for wake up signal
Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

targets/RT/USER/lte-enb.c

@@ -515,17 +515,16 @@ int wakeup_txfh(PHY_VARS_eNB *eNB, L1_rxtx_proc_t *proc,int frame_tx,int subfram
        continue;//hacking only works when all RU_tx works on the same subframe #TODO: adding mask stuff
     }
 
-    AssertFatal((ret = pthread_mutex_lock(&ru_proc->mutex_eNBs))==0,"ERROR pthread_mutex_lock failed on mutex_eNBs L1_thread_tx with ret=%d\n",ret);
-
     if (ru_proc->instance_cnt_eNBs == 0) {
       LOG_E(PHY,"Frame %d, subframe %d: TX FH thread busy, dropping Frame %d, subframe %d\n", ru_proc->frame_tx, ru_proc->subframe_tx, proc->frame_rx, proc->subframe_rx);
       AssertFatal((ret=pthread_mutex_lock(&eNB->proc.mutex_RU_tx))==0,"mutex_lock returns %d\n",ret);
       eNB->proc.RU_mask_tx = 0;
       AssertFatal((ret=pthread_mutex_unlock(&eNB->proc.mutex_RU_tx))==0,"mutex_unlock returns %d\n",ret);
-      AssertFatal((ret=pthread_mutex_unlock( &ru_proc->mutex_eNBs ))==0,"mutex_unlock return %d\n",ret);
       return(-1);
     }
 
+    AssertFatal((ret = pthread_mutex_lock(&ru_proc->mutex_eNBs))==0,"ERROR pthread_mutex_lock failed on mutex_eNBs L1_thread_tx with ret=%d\n",ret);
+
     ru_proc->instance_cnt_eNBs = 0;
     ru_proc->timestamp_tx = timestamp_tx;
     ru_proc->subframe_tx  = subframe_tx;