pb-1997: Added check not to intialize the snapshot class in the DE, if CSI does not support snapshot or cases where we want to skip CSI and take generic backup (proxy-volume)
pb-1997: Added check not to intialize the snapshot class in the DE, if
CSI does not support snapshot or cases where we want to skip CSI and
take generic backup (proxy-volume)

libopenstorage/stork,libopenstorage/stork,libopenstorage/stork