scsi: scsi_debug: Make pseudo_lld_bus const

Now that the driver core can properly handle constant struct bus_type, move
the pseudo_lld_bus 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>
Link: https://lore.kernel.org/r/20240203-bus_cleanup-scsi-v1-3-6f552fb24f71@marliere.netReviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/scsi_debug.c

@@ -899,7 +899,7 @@ static int poll_queues; /* iouring iopoll interface.*/
 static char sdebug_proc_name[] = MY_NAME;
 static const char *my_name = MY_NAME;
 
-static struct bus_type pseudo_lld_bus;
+static const struct bus_type pseudo_lld_bus;
 
 static struct device_driver sdebug_driverfs_driver = {
 	.name 		= sdebug_proc_name,
@@ -8405,7 +8405,7 @@ static void sdebug_driver_remove(struct device *dev)
 	scsi_host_put(sdbg_host->shost);
 }
 
-static struct bus_type pseudo_lld_bus = {
+static const struct bus_type pseudo_lld_bus = {
 	.name = "pseudo",
 	.probe = sdebug_driver_probe,
 	.remove = sdebug_driver_remove,