btrfs-progs: close all fs_devices before exit in some commands

mkfs creates more than one fs_devices in fs_uuids.
1: one is for file system being created
2: others are created in test_dev_for_mkfs in order to check mount point
   test_dev_for_mkfs()-> ... -> btrfs_scan_one_device()

Current code only closes 1, and this patch also closes in case 2.

Similar problem exist in other tools, eg.::

 cmd-check.c: the function is:
 cmd_check()->check_mounted()-> ... -> btrfs_scan_one_device()
 ...

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/mkfs.c b/mkfs.c
index 7d635dc..3e60965 100644
--- a/mkfs.c
+++ b/mkfs.c
@@ -1843,6 +1843,7 @@ raid_groups:
 out:
 	ret = close_ctree(root);
 	BUG_ON(ret);
+	btrfs_close_all_devices();
 	free(label);
 	return 0;
 }