most: core: make mostbus const

Now that the driver core can properly handle constant struct bus_type,
move the mostbus 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/20240204-bus_cleanup-most-v1-1-f5cd9a06e13f@marliere.netSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/most/core.c

@@ -499,7 +499,7 @@ static int most_match(struct device *dev, struct device_driver *drv)
 		return 1;
 }
 
-static struct bus_type mostbus = {
+static const struct bus_type mostbus = {
 	.name = "most",
 	.match = most_match,
 };