xfs: call xfs_iformat_fork from xfs_inode_from_disk

We always need to fill out the fork structures when reading the inode,
so call xfs_iformat_fork from the tail of xfs_inode_from_disk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>