erofs: make kobj_type structures constant

Since commit ee6d3dd ("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 definitions to prevent
modification at runtime.

Signed-off-by: Thomas Weißschuh <[email protected]>
Acked-by: Gao Xiang <[email protected]>
Reviewed-by: Jingbo Xu <[email protected]>
Reviewed-by: Yue Hu <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Gao Xiang <[email protected]>

fs/erofs/sysfs.c

@@ -179,21 +179,21 @@ static const struct sysfs_ops erofs_attr_ops = {
 	.store	= erofs_attr_store,
 };
 
-static struct kobj_type erofs_sb_ktype = {
+static const struct kobj_type erofs_sb_ktype = {
 	.default_groups = erofs_groups,
 	.sysfs_ops	= &erofs_attr_ops,
 	.release	= erofs_sb_release,
 };
 
-static struct kobj_type erofs_ktype = {
+static const struct kobj_type erofs_ktype = {
 	.sysfs_ops	= &erofs_attr_ops,
 };
 
 static struct kset erofs_root = {
 	.kobj	= {.ktype = &erofs_ktype},
 };
 
-static struct kobj_type erofs_feat_ktype = {
+static const struct kobj_type erofs_feat_ktype = {
 	.default_groups = erofs_feat_groups,
 	.sysfs_ops	= &erofs_attr_ops,
 };