Fix stream unittests.

src/stream-tcp-reassemble.c

@@ -148,10 +148,13 @@ void StreamTcpReassembleDecrMemuse(uint64_t size) {
 }
 
 void StreamTcpReassembleMemuseCounter(ThreadVars *tv, TcpReassemblyThreadCtx *rtv) {
+    if (tv != NULL && rtv != NULL) {
         SCSpinLock(&stream_reassembly_memuse_spinlock);
-    SCPerfCounterSetUI64(rtv->counter_tcp_reass_memuse, tv->sc_perf_pca, stream_reassembly_memuse);
+        SCPerfCounterSetUI64(rtv->counter_tcp_reass_memuse, tv->sc_perf_pca,
+                stream_reassembly_memuse);
         SCSpinUnlock(&stream_reassembly_memuse_spinlock);
     }
+}
 
 /**
  * \brief  Function to Check the reassembly memory usage counter against the