xfs: clean up xfs_end_ioend() to reuse local variables

xfs: clean up xfs_end_ioend() to reuse local variables

Use already initialized local variables 'offset' and 'size' instead
of accessing ioend members directly in xfs_setfilesize() call.

This is just a code cleanup with no functional changes.

Signed-off-by: Long Li <leo.lilong@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>