xfs: pass an initialized xfs_da_args to xfs_attr_get

xfs: pass an initialized xfs_da_args to xfs_attr_get

Source kernel commit: e5171d7e989479fe6298f8aedbd94e0aec23f5fc

Instead of converting from one style of arguments to another in
xfs_attr_set, pass the structure from higher up in the call chain.

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>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>