Fix DRBD version check for non VM capable nodes
Fix DRBD version check for non VM capable nodes

Commit 742dc8de revealed a bug concerning DRBD version check during
cluster verify: In case non VM cabables nodes have DRBD not
installed, we get a version mismatch warning.

VerifyNode() updates the NV_DRBDVERSION key in the response message
only if a node is VM capable. Even if noded fails to retrieve the
DRBD version, the error string is returned.

Thus we must first check in _VerifyGroupDRBDVersion() if the
NV_DRBDVERSION key of the response message is updated and
then verify if we have different versions across nodes.

Signed-off-by: Dimitris Aragiorgis <4514117c4a99256e19437c7e3407c4ecbf98aec0@grnet.gr>
Signed-off-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>
Reviewed-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>

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