Update gnt-cluster man page for removal of --hypervisor-type.
Update gnt-cluster man page for removal of --hypervisor-type.

We no longer use a single, cluster-wide hypervisor, but configure the
actual to be used hypervisor on the instance level. The option has already
been removed from gnt-cluster.

Reviewed-by: imsnah



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