Do not start threads in detached mode. Joining them may SEGFAULT with libmusl

Signed-off-by: DL6ER <dl6er@dl6er.de>

src/dnsmasq_interface.c

@@ -2912,12 +2912,10 @@ void FTL_fork_and_bind_sockets(struct passwd *ent_pw, bool dnsmasq_start)
 	// so they will not listen to real-time signals
 	handle_realtime_signals();
 
-	// We will use the attributes object later to start all threads in
-	// detached mode
-	pthread_attr_t attr;
 	// Initialize thread attributes object with default attribute values
 	// Do NOT detach threads as we want to join them during shutdown with a
 	// fixed timeout to give them time to clean up and finish their work
+	pthread_attr_t attr;
 	pthread_attr_init(&attr);
 
 	// Initialize NTP server

src/tools/arp-scan.c

@@ -616,8 +616,6 @@ int run_arp_scan(const bool scan_all, const bool extreme_mode)
 	pthread_attr_t attr;
 	// Initialize thread attributes object with default attribute values
 	pthread_attr_init(&attr);
-	// Set thread attributes to detached mode
-	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
 
 	struct ifaddrs *addrs, *tmp;
 	getifaddrs(&addrs);

src/tools/dhcp-discover.c

@@ -725,8 +725,6 @@ int run_dhcp_discover(void)
 	pthread_attr_t attr;
 	// Initialize thread attributes object with default attribute values
 	pthread_attr_init(&attr);
-	// Set thread attributes to detached mode
-	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
 
 	// Create processing/printfing lock
 	pthread_mutexattr_t lock_attr;