MIPS: ralink: bootrom: mark a function as __init to save some memory

'bootrom_setup()' is only called via 'postcore_initcall'.
It can be marked as __init to save a few bytes of memory.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/ralink/bootrom.c

@@ -31,7 +31,7 @@ static const struct file_operations bootrom_file_ops = {
 	.release	= single_release,
 };
 
-static int bootrom_setup(void)
+static int __init bootrom_setup(void)
 {
 	debugfs_create_file("bootrom", 0444, NULL, NULL, &bootrom_file_ops);
 	return 0;