Recently the k8s.io/mount-utils package added more runtime dectection.
When creating a new Mounter, the detect is run every time. This is
unfortunate, as it logs a message like the following:
```
mount_linux.go:283] Detected umount with safe 'not mounted' behavior
```
This message might be useful, so it probably good to keep it.
In Ceph-CSI there are various locations where Mounter instances are
created. Moving that to the DefaultNodeServer type reduces it to a
single place. Some utility functions need to accept the additional
parameter too, so that has been modified as well.
See-also: kubernetes/kubernetes#109676
Signed-off-by: Niels de Vos <ndevos@redhat.com>