xfs: fix copy-paste error in previous fix

xfs: fix copy-paste error in previous fix

Chris Mason noticed that there is a copy-paste error in a recent change
to xrep_dir_teardown that nulls out pointers after freeing the
resources.

Fixes: ba408d299a3bb3c ("xfs: only call xf{array,blob}_destroy if we have a valid pointer")
Link: https://lore.kernel.org/linux-xfs/20260205194211.2307232-1-clm@meta.com/
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Carlos Maiolino <cem@kernel.org>