Add configuration infrastructure

Rather than expecting parameters on the command line, this change
implemnets a little configration infrastructure, to allow the core
code to load configuration from a file in ${sysconfdir}.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
diff --git a/console-server.h b/console-server.h
index 292b54a..dcedada 100644
--- a/console-server.h
+++ b/console-server.h
@@ -48,6 +48,12 @@
 
 void console_unregister_poller(struct console *console, struct poller *poller);
 
+/* config API */
+struct config;
+const char *config_get_value(struct config *config, const char *name);
+struct config *config_init(const char *filename);
+void config_fini(struct config *config);
+
 /* socket paths */
 const char *console_socket_path;
 const size_t console_socket_path_len;