qcow2: Fix qcow2_truncate() error return value

If qcow2_alloc_clusters_at() returns an error, we do need to negate it
to get back the positive errno code for error_setg_errno(), but we still
need to return the negative error code.

Fixes: 772d1f973f87269f6a4a4ea4b880680f3779bbdf
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
1 file changed