VTY: pass program name, version and copyright to vty_init()

This enables us to make the VTY completely independent of any
compile-time program-specific information, i.e. one step closer
to using VTY as a shared library from multiple programs.
diff --git a/openbsc/include/vty/vty.h b/openbsc/include/vty/vty.h
index 0441fc5..23430d5 100644
--- a/openbsc/include/vty/vty.h
+++ b/openbsc/include/vty/vty.h
@@ -128,7 +128,7 @@
 }
 
 /* Prototypes. */
-void vty_init (void);
+void vty_init(const char *name, const char *version, const char *copyright);
 int vty_read_config_file(const char *file_name);
 void vty_init_vtysh (void);
 void vty_reset (void);