session server BUGFIX lock config wrlock

Author: Roytak

src/session_server.c

@@ -243,11 +243,17 @@ nc_server_ch_set_dispatch_data(nc_server_ch_session_acquire_ctx_cb acquire_ctx_c
 {
     NC_CHECK_ARG_RET(NULL, acquire_ctx_cb, release_ctx_cb, new_session_cb, );
 
+    /* CONFIG WRITE LOCK */
+    pthread_rwlock_wrlock(&server_opts.config_lock);
+
     server_opts.ch_dispatch_data.acquire_ctx_cb = acquire_ctx_cb;
     server_opts.ch_dispatch_data.release_ctx_cb = release_ctx_cb;
     server_opts.ch_dispatch_data.ctx_cb_data = ctx_cb_data;
     server_opts.ch_dispatch_data.new_session_cb = new_session_cb;
     server_opts.ch_dispatch_data.new_session_cb_data = new_session_cb_data;
+
+    /* CONFIG WRITE UNLOCK */
+    pthread_rwlock_unlock(&server_opts.config_lock);
 }
 
 #endif