btrfs: refactor btrfs_find_device() take fs_devices as argument

btrfs_find_device() accepts fs_info as an argument and retrieves
fs_devices from fs_info.

Instead use fs_devices, so that this function can be used in non-mount
(during device scanning) context as well.

Signed-off-by: Anand Jain <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
5 files changed