[XFS] Fix XFS_IOC_FSBULKSTAT{,_SINGLE} & XFS_IOC_FSINUMBERS in compat mode

[XFS] Fix XFS_IOC_FSBULKSTAT{,_SINGLE} & XFS_IOC_FSINUMBERS in compat mode

* 32bit struct xfs_fsop_bulkreq has different size and layout of
members, no matter the alignment. Move the code out of the #else
branch (why was it there in the first place?). Define _32 variants of
the ioctl constants.
* 32bit struct xfs_bstat is different because of time_t and on
i386 because of different padding. Make xfs_bulkstat_one() accept a
custom "output formatter" in the private_data argument which takes care
of the xfs_bulkstat_one_compat() that takes care of the different
layout in the compat case.
* i386 struct xfs_inogrp has different padding.
Add a similar "output formatter" mecanism to xfs_inumbers().

SGI-PV: 967354
SGI-Modid: xfs-linux-melb:xfs-kern:29102a

Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>