CLEANUP: da: register the deinitialization function

deinit_deviceatlas() is not called anymore from haproxy.c, removing 2
still includes other parts of the Deviceatlas library so it was not
touched.
diff --git a/src/da.c b/src/da.c
index 843da9f..9ea266f 100644
--- a/src/da.c
+++ b/src/da.c
@@ -146,7 +146,7 @@
 	return err_code;
 }
 
-void deinit_deviceatlas(void)
+static void deinit_deviceatlas(void)
 {
 	if (global.deviceatlas.jsonpath != 0) {
 		free(global.deviceatlas.jsonpath);
@@ -374,4 +374,5 @@
 	cfg_register_keywords(&dacfg_kws);
 	hap_register_build_opts("Built with DeviceAtlas support.", 0);
 	hap_register_post_check(init_deviceatlas);
+	hap_register_post_deinit(deinit_deviceatlas);
 }