cephfs: support selinux mount options

- mount host's /etc/selinux in node plugins
- process mount options in all code paths for cephfs volume options

Signed-off-by: Alexandre Lossent <alexandre.lossent@cern.ch>

internal/cephfs/volumeoptions.go

@@ -411,6 +411,14 @@ func newVolumeOptionsFromMonitorList(
 		}
 	}
 
+	if err = extractOptionalOption(&opts.KernelMountOptions, "kernelMountOptions", options); err != nil {
+		return nil, nil, err
+	}
+
+	if err = extractOptionalOption(&opts.FuseMountOptions, "fuseMountOptions", options); err != nil {
+		return nil, nil, err
+	}
+
 	if err = extractMounter(&opts.Mounter, options); err != nil {
 		return nil, nil, err
 	}