xfs: embedded the attrlist cursor into struct xfs_attr_list_context
The attrlist cursor only exists as part of an attr list context, so
embedd the structure instead of pointing to it. Also give it a proper
xfs_ prefix and remove the obsolete typedef.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>