xfstests: ignore absolute address in filename in test case 237

[Boris Ranto]

----- "Christoph Hellwig" <hch at infradead.org> wrote:

> I don't mind the patch, but what version of getfacl would produce an
> absolute filename?

The behavior was found in acl-2.2.39-6.el5:

* setfacl -m 'user:test:rw' file 
setfacl: /mnt/tests/kernel/filesystems/xfs/xfstests/file: Operation not permitted
* setfacl --version
setfacl 2.2.39