xfs: rework deferred attribute operation setup

Logged attribute intents only have set and remove types - there is
no separate intent type for a replace operation. We should have a
separate type for a replace operation, as it needs to perform
operations that neither SET or REMOVE can perform.

Add this type to the intent items and rearrange the deferred
operation setup to reflect the different operations we are
performing.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison <Henderson&lt;allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>