nghttp: Fix crash on plain HTTP

src/nghttp.cc

@@ -1313,6 +1313,7 @@ void eventcb(bufferevent *bev, short events, void *ptr)
     if(client->need_upgrade()) {
       rv = client->on_upgrade_connect();
     } else {
+      if(client->ssl) {
         // Check NPN or ALPN result
         const unsigned char *next_proto = nullptr;
         unsigned int next_proto_len;
@@ -1344,6 +1345,7 @@ void eventcb(bufferevent *bev, short events, void *ptr)
           client->disconnect();
           return;
         }
+      }
       rv = client->on_connect();
     }
     if(rv != 0) {