module: make module_ktype structure constant

Since commit ee6d3dd4 ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.

Take advantage of this to constify the structure definition to prevent
modification at runtime.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

include/linux/module.h

@@ -871,7 +871,7 @@ void *dereference_module_function_descriptor(struct module *mod, void *ptr)
 
 #ifdef CONFIG_SYSFS
 extern struct kset *module_kset;
-extern struct kobj_type module_ktype;
+extern const struct kobj_type module_ktype;
 #endif /* CONFIG_SYSFS */
 
 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)

kernel/params.c

@@ -948,7 +948,7 @@ static void module_kobj_release(struct kobject *kobj)
 	complete(mk->kobj_completion);
 }
 
-struct kobj_type module_ktype = {
+const struct kobj_type module_ktype = {
 	.release   =	module_kobj_release,
 	.sysfs_ops =	&module_sysfs_ops,
 };