fix use after free

dns_client_exit does release the server_info members which are accessed
in dns_server_exit by _dns_server_close_socket
this leads to a crash at program exit or any other call of
_smartdns_exiti

Jan 31 08:10:11.005 dd-wrt user.emerg smartdns: process exit with signal 11, code = 1, errno = 0, pid = -1599429336, self = 7199, pc = 0x7fa132a640, addr = 0x7fa0aaa528, build(Jan 31 2026 07:01:24 arm64)
Jan 31 08:10:11.006 dd-wrt user.emerg smartdns: Stack:
Jan 31 08:10:11.006 dd-wrt user.emerg smartdns: #1: 0x41a650 print_stack() from /usr/sbin/smartdns+0x1a650
Jan 31 08:10:11.006 dd-wrt user.emerg smartdns: #2: 0x41a790 () from /usr/sbin/smartdns+0x1a790
Jan 31 08:10:11.006 dd-wrt user.emerg smartdns: #3: 0x7fa131a964 __setjmp() from /lib/ld-musl-aarch64.so.1+0x4a964
Jan 31 08:10:11.006 dd-wrt user.emerg smartdns: #4: 0x7fa132a640 () from /lib/ld-musl-aarch64.so.1+0x5a640

Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>

Author: BrainSlayer

src/smartdns.c

@@ -714,10 +714,10 @@ static int _smartdns_run(void)
 static void _smartdns_exit(void)
 {
 	_smartdns_plugin_exit();
-	dns_client_exit();
 	proxy_exit();
 	fast_ping_exit();
 	dns_server_exit();
+	dns_client_exit();
 	dns_stats_exit();
 	_smartdns_destroy_ssl();
 	dns_timer_destroy();