net: a few small cleanups before replacing boost threads

- Drop the interruption point directly after the pnode allocation. This would
    be leaky if hit.
- Rearrange thread creation so that the socket handler comes first

src/net.cpp

@@ -1739,7 +1739,6 @@ bool CConnman::OpenNetworkConnection(const CAddress& addrConnect, bool fCountFai
         return false;
 
     CNode* pnode = ConnectNode(addrConnect, pszDest, fCountFailure);
-    boost::this_thread::interruption_point();
 
     if (!pnode)
         return false;
@@ -2034,14 +2033,14 @@ bool CConnman::Start(boost::thread_group& threadGroup, CScheduler& scheduler, st
     // Start threads
     //
 
+    // Send and receive from sockets, accept connections
+    threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "net", boost::function<void()>(boost::bind(&CConnman::ThreadSocketHandler, this))));
+
     if (!GetBoolArg("-dnsseed", true))
         LogPrintf("DNS seeding disabled\n");
     else
         threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "dnsseed", boost::function<void()>(boost::bind(&CConnman::ThreadDNSAddressSeed, this))));
 
-    // Send and receive from sockets, accept connections
-    threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "net", boost::function<void()>(boost::bind(&CConnman::ThreadSocketHandler, this))));
-
     // Initiate outbound connections from -addnode
     threadGroup.create_thread(boost::bind(&TraceThread<boost::function<void()> >, "addcon", boost::function<void()>(boost::bind(&CConnman::ThreadOpenAddedConnections, this))));