[init] Show startup and shutdown function names in debug messages

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/include/ipxe/init.h

@@ -39,6 +39,7 @@ struct init_fn {
  * part of the calls to startup() and shutdown().
  */
 struct startup_fn {
+	const char *name;
 	void ( * startup ) ( void );
 	void ( * shutdown ) ( int booting );
 };