Safer fix for make_update.py on buildbot

Makes it so compilation doesn't fail when the SVN updating
stumbles upon checkout which doesn't have correspondence in
a tag, but which isn't so risky as previous change.

build_files/utils/make_update.py

@@ -108,7 +108,7 @@ def svn_update(args, release_version):
             if os.path.exists(svn_dirpath):
                 call(svn_non_interactive + ["cleanup", dirpath])
             # Switch to appropriate branch and update.
-            call(svn_non_interactive + ["switch", svn_url + dirname, dirpath])
+            call(svn_non_interactive + ["switch", svn_url + dirname, dirpath], exit_on_error=False)
             call(svn_non_interactive + ["update", dirpath])
 
 # Test if git repo can be updated.