vty: Make the argument const
diff --git a/openbsc/src/vty/command.c b/openbsc/src/vty/command.c
index f03dcbb..c32e703 100644
--- a/openbsc/src/vty/command.c
+++ b/openbsc/src/vty/command.c
@@ -3311,7 +3311,7 @@
 }
 
 /* Set config filename.  Called from vty.c */
-void host_config_set(char *filename)
+void host_config_set(const char *filename)
 {
 	host.config = talloc_strdup(tall_vty_ctx, filename);
 }