rbd: disable reflink while creating XFS filesystems
rbd: disable reflink while creating XFS filesystems

Current versions of the mkfs.xfs binary enable reflink support by
default. This causes problems on systems where the kernel does not
support this feature. When the kernel the feature does not support, but
the filesystem has it enabled, the following error is logged in `dmesg`:

    XFS: Superblock has unknown read-only compatible features (0x4) enabled

Introduce a check to see if mkfs.xfs supports the `-m reflink=` option.
In case it does, pass `-m reflink=0` while creating the filesystem.

The check is executed once during the first XFS filesystem creation. The
result of the check is cached until the nodeserver restarts.

Fixes: #966
Signed-off-by: Niels de Vos <7bda0c0ee7f47171cc808e9e60292cbc5d8140dd@redhat.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi