Remove unneeded link and import
Remove unneeded link and import

The btrfs library does not require linking against libbtrfs
since only structures defined in the headers are used. Compiling
will still require btrfs headers.

Signed-off-by: Derek McGowan <e1c79a582b6629e6b39e9679f4bb964d25db4aa8@mcgstyle.net>

stevvooe/go-btrfs,stevvooe/go-btrfs