btrfs: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/btrfs/sysfs.c

@@ -910,12 +910,10 @@ void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
 	ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
 }
 
-static int btrfs_init_debugfs(void)
+static void btrfs_init_debugfs(void)
 {
 #ifdef CONFIG_DEBUG_FS
 	btrfs_debugfs_root_dentry = debugfs_create_dir("btrfs", NULL);
-	if (!btrfs_debugfs_root_dentry)
-		return -ENOMEM;
 
 	/*
 	 * Example code, how to export data through debugfs.
@@ -929,7 +927,6 @@ static int btrfs_init_debugfs(void)
 #endif
 
 #endif
-	return 0;
 }
 
 int __init btrfs_init_sysfs(void)
@@ -940,9 +937,7 @@ int __init btrfs_init_sysfs(void)
 	if (!btrfs_kset)
 		return -ENOMEM;
 
-	ret = btrfs_init_debugfs();
-	if (ret)
-		goto out1;
+	btrfs_init_debugfs();
 
 	init_feature_attrs();
 	ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
@@ -959,7 +954,6 @@ int __init btrfs_init_sysfs(void)
 	sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
 out2:
 	debugfs_remove_recursive(btrfs_debugfs_root_dentry);
-out1:
 	kset_unregister(btrfs_kset);
 
 	return ret;