Add (unused) arg to _OfflineClusterMerge
Add (unused) arg to _OfflineClusterMerge

cli._RunWhileClusterStoppedHelper.Call passes (self, *args) to functions
called via cli.RunWhileClusterStoppedHelper(). The code in cluster-merge
was broken by commit d8aab233.

Signed-off-by: Stephen Shirley <f872caad177d67bbe18c119d0505f2d3caa02af3@google.com>
Signed-off-by: Iustin Pop <acf83a5274f31a43af6b914614365999469c1a31@google.com>
Reviewed-by: Iustin Pop <acf83a5274f31a43af6b914614365999469c1a31@google.com>

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