btrfs: export and rename free_device

The function will be used outside of volumes.c, the allocation
btrfs_alloc_device is also exported.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2018-03-20 15:47:33 +01:00
commit a425f9d475
2 changed files with 13 additions and 12 deletions