ovl: fix typo in MODULE_PARM_DESC

Change first argument to MODULE_PARM_DESC() calls, that each of them
matched the actual module parameter name.  The matching results in
changing (the 'parm' section from) the output of `modinfo overlay` from:

    parm: ovl_check_copy_up:Obsolete; does nothing
    parm: redirect_max:ushort
    parm: ovl_redirect_max:Maximum length of absolute redirect xattr value
    parm: redirect_dir:bool
    parm: ovl_redirect_dir_def:Default to on or off for the redirect_dir feature
    parm: redirect_always_follow:bool
    parm: ovl_redirect_always_follow:Follow redirects even if redirect_dir feature is turned off
    parm: index:bool
    parm: ovl_index_def:Default to on or off for the inodes index feature
    parm: nfs_export:bool
    parm: ovl_nfs_export_def:Default to on or off for the NFS export feature
    parm: xino_auto:bool
    parm: ovl_xino_auto_def:Auto enable xino feature
    parm: metacopy:bool
    parm: ovl_metacopy_def:Default to on or off for the metadata only copy up feature

into:

    parm: check_copy_up:Obsolete; does nothing
    parm: redirect_max:Maximum length of absolute redirect xattr value (ushort)
    parm: redirect_dir:Default to on or off for the redirect_dir feature (bool)
    parm: redirect_always_follow:Follow redirects even if redirect_dir feature is turned off (bool)
    parm: index:Default to on or off for the inodes index feature (bool)
    parm: nfs_export:Default to on or off for the NFS export feature (bool)
    parm: xino_auto:Auto enable xino feature (bool)
    parm: metacopy:Default to on or off for the metadata only copy up feature (bool)
Signed-off-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

fs/overlayfs/copy_up.c

@@ -37,7 +37,7 @@ static int ovl_ccup_get(char *buf, const struct kernel_param *param)
 }
 
 module_param_call(check_copy_up, ovl_ccup_set, ovl_ccup_get, NULL, 0644);
-MODULE_PARM_DESC(ovl_check_copy_up, "Obsolete; does nothing");
+MODULE_PARM_DESC(check_copy_up, "Obsolete; does nothing");
 
 int ovl_copy_xattr(struct dentry *old, struct dentry *new)
 {

fs/overlayfs/dir.c

@@ -21,7 +21,7 @@
 
 static unsigned short ovl_redirect_max = 256;
 module_param_named(redirect_max, ovl_redirect_max, ushort, 0644);
-MODULE_PARM_DESC(ovl_redirect_max,
+MODULE_PARM_DESC(redirect_max,
 		 "Maximum length of absolute redirect xattr value");
 
 static int ovl_set_redirect(struct dentry *dentry, bool samedir);

fs/overlayfs/super.c

@@ -31,29 +31,29 @@ struct ovl_dir_cache;
 
 static bool ovl_redirect_dir_def = IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_DIR);
 module_param_named(redirect_dir, ovl_redirect_dir_def, bool, 0644);
-MODULE_PARM_DESC(ovl_redirect_dir_def,
+MODULE_PARM_DESC(redirect_dir,
 		 "Default to on or off for the redirect_dir feature");
 
 static bool ovl_redirect_always_follow =
 	IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW);
 module_param_named(redirect_always_follow, ovl_redirect_always_follow,
 		   bool, 0644);
-MODULE_PARM_DESC(ovl_redirect_always_follow,
+MODULE_PARM_DESC(redirect_always_follow,
 		 "Follow redirects even if redirect_dir feature is turned off");
 
 static bool ovl_index_def = IS_ENABLED(CONFIG_OVERLAY_FS_INDEX);
 module_param_named(index, ovl_index_def, bool, 0644);
-MODULE_PARM_DESC(ovl_index_def,
+MODULE_PARM_DESC(index,
 		 "Default to on or off for the inodes index feature");
 
 static bool ovl_nfs_export_def = IS_ENABLED(CONFIG_OVERLAY_FS_NFS_EXPORT);
 module_param_named(nfs_export, ovl_nfs_export_def, bool, 0644);
-MODULE_PARM_DESC(ovl_nfs_export_def,
+MODULE_PARM_DESC(nfs_export,
 		 "Default to on or off for the NFS export feature");
 
 static bool ovl_xino_auto_def = IS_ENABLED(CONFIG_OVERLAY_FS_XINO_AUTO);
 module_param_named(xino_auto, ovl_xino_auto_def, bool, 0644);
-MODULE_PARM_DESC(ovl_xino_auto_def,
+MODULE_PARM_DESC(xino_auto,
 		 "Auto enable xino feature");
 
 static void ovl_entry_stack_free(struct ovl_entry *oe)
@@ -66,7 +66,7 @@ static void ovl_entry_stack_free(struct ovl_entry *oe)
 
 static bool ovl_metacopy_def = IS_ENABLED(CONFIG_OVERLAY_FS_METACOPY);
 module_param_named(metacopy, ovl_metacopy_def, bool, 0644);
-MODULE_PARM_DESC(ovl_metacopy_def,
+MODULE_PARM_DESC(metacopy,
 		 "Default to on or off for the metadata only copy up feature");
 
 static void ovl_dentry_release(struct dentry *dentry)