ALSA: seq: make snd_seq_bus_type const

Since commit d492cc25 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the snd_seq_bus_type variable to be a constant
structure as well, placing it into read-only memory which can not be
modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240214-bus_cleanup-alsa-v1-2-8fedbb4afa94@marliere.netSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/seq_device.c

@@ -49,7 +49,7 @@ static int snd_seq_bus_match(struct device *dev, struct device_driver *drv)
 		sdrv->argsize == sdev->argsize;
 }
 
-static struct bus_type snd_seq_bus_type = {
+static const struct bus_type snd_seq_bus_type = {
 	.name = "snd_seq",
 	.match = snd_seq_bus_match,
 };