Delete a cg-snapshot following updated volumes

This patch is uploaded, since there is a bug report,
while trying to delete a cg-snapshot that is based on an
updated volume group the cg-snapshot stuck in deleting status.

Note: When dealing with consistency groups all volumes must
reside on the same backend. Adding volumes to the same consistency
group from multiple backends isn't supported. In order to ensure all
volumes share the same backend, all volumes must share same
volume-type and group id.

Related-Bug: #1739031
Change-Id: I70997acdf5d0e962ba863c3410ef0b13c195807e
1 file changed