ALSA: aoa: constify of_device_id array

of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/aoa/soundbus/i2sbus/core.c

@@ -31,7 +31,7 @@ module_param(force, int, 0444);
 MODULE_PARM_DESC(force, "Force loading i2sbus even when"
 			" no layout-id property is present");
 
-static struct of_device_id i2sbus_match[] = {
+static const struct of_device_id i2sbus_match[] = {
 	{ .name = "i2s" },
 	{ }
 };