The internal/csi-common package offers helper functions like
`IsReaderOnly()` and `IsBlockMultiNode()`. These should be used instead
of checking the VolumeCapability that is passed in a request in
different places.
This also suggested that adding the "ro" mount option in
`NodeServer.mountVolumeToStagePath()` is not appropriate, as the
csi-common helper `ConstructMountOptions()` can take care of that
already too.
Signed-off-by: Niels de Vos <ndevos@ibm.com>
ea7be34396