unix-socket: fix restart/shutdown cycle

When cleaning up after a pcap was processed, the stats api was cleaned
up before the stats threads were killed, leading to a BUG_ON triggering.

src/runmode-unix-socket.c

@@ -295,13 +295,14 @@ TmEcode UnixSocketPcapFilesCheck(void *data)
         TmThreadKillThreadsFamily(TVT_PPT);
         TmThreadClearThreadsFamily(TVT_PPT);
         FlowKillFlowRecyclerThread();
-        RunModeShutDown();
 
         /* kill remaining mgt threads */
         TmThreadKillThreadsFamily(TVT_MGMT);
         TmThreadClearThreadsFamily(TVT_MGMT);
         SCPerfReleaseResources();
 
+        RunModeShutDown();
+
         /* mgt and ppt threads killed, we can run non thread-safe
          * shutdown functions */
         FlowShutdown();