Make userspace access checks properly strict
Make userspace access checks properly strict

When a cluster- or group-level disk template access mode change is
specified, Ganeti makes sure that this change would not lead to an
invalid hypervisor/access mode combination on an existing instance.
This check was extended to non-RBD disk templates in patch 6488e5bc,
but was overly broad, targeting disk templates for which the
parameter was not set. This patch fixes the check.

Signed-off-by: Hrvoje Ribicic <be5828fca31f89218048bec4189e30a581aa65da@google.com>
Reviewed-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>

ganeti/ganeti,onponomarev/ganeti,dimara/ganeti,bitemyapp/ganeti,andir/ganeti,leshchevds/ganeti,leshchevds/ganeti,dimara/ganeti,mbakke/ganeti,onponomarev/ganeti,mbakke/ganeti,andir/ganeti,apyrgio/ganeti,yiannist/ganeti,andir/ganeti,yiannist/ganeti,ganeti/ganeti,leshchevds/ganeti,apyrgio/ganeti,ganeti-github-testing/ganeti-test-1,mbakke/ganeti,ganeti-github-testing/ganeti-test-1,yiannist/ganeti,grnet/snf-ganeti,bitemyapp/ganeti,grnet/snf-ganeti,ganeti/ganeti