add two asserts to help parfait (#2530)

From: Stefan Bühler <stbuehler@web.de>

git-svn-id: svn://svn.lighttpd.net/lighttpd/branches/lighttpd-1.4.x@2931 152afb58-edef-0310-8abb-c4023f1b3aa9

src/array.c

@@ -170,6 +170,7 @@ void array_set_key_value(array *hdrs, const char *key, size_t key_len, const cha
 data_unset *array_replace(array *a, data_unset *du) {
 	int ndx;
 
+	assert(NULL != du);
 	if (-1 == (ndx = array_get_index(a, du->key->ptr, du->key->used, NULL))) {
 		array_insert_unique(a, du);
 		return NULL;

src/configfile.c

@@ -1170,6 +1170,7 @@ int config_read(server *srv, const char *fn) {
 		}
 
 		prepends = (data_array *)configparser_merge_data((data_unset *)prepends, (data_unset *)modules);
+		assert(NULL != prepends);
 		buffer_copy_string_buffer(prepends->key, modules->key);
 		array_replace(srv->config, (data_unset *)prepends);
 		modules->free((data_unset *)modules);