pNFS/filelayout: fixup pNfs allocation modes

Change left over allocation flags.

Fixes: a245832a ("pNFS/files: Ensure pNFS allocation modes are consistent with nfsiod")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>