Move freeing the dynamically allocated attr and COW fork, as well
as zeroing the pointers where actually needed into the callers, and
just pass the xfs_ifork structure to xfs_idestroy_fork.  Also simplify
the kmem_free calls by not checking for NULL first.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NChandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>