xfs: pass struct xfs_eofblocks to the inode scan callback

Pass a pointer to the actual eofb structure around the inode scanner
functions instead of a void pointer, now that none of the functions is
used as a callback.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>