stream: memcap tracking for TcpSegment alloc

src/stream-tcp-reassemble.c

@@ -291,6 +291,8 @@ static void *TcpSegmentPoolAlloc(void)
                 return NULL;
             }
         }
+
+        StreamTcpReassembleIncrMemuse(memuse);
     } else {
         seg->pcap_hdr_storage = NULL;
     }