Check interruptNet during dnsseed lookups

src/net.cpp

@@ -1579,6 +1579,9 @@ void CConnman::ThreadDNSAddressSeed()
     LogPrintf("Loading addresses from DNS seeds (could take a while)\n");
 
     BOOST_FOREACH(const CDNSSeedData &seed, vSeeds) {
+        if (interruptNet) {
+            return;
+        }
         if (HaveNameProxy()) {
             AddOneShot(seed.host);
         } else {
@@ -1596,6 +1599,9 @@ void CConnman::ThreadDNSAddressSeed()
                     found++;
                 }
             }
+            if (interruptNet) {
+                return;
+            }
             // TODO: The seed name resolve may fail, yielding an IP of [::], which results in
             // addrman assigning the same source to results from different seeds.
             // This should switch to a hard-coded stable dummy IP for each seed name, so that the