Never ever use distributed lock for LV in non-clustered VG.

Never ever use distributed lock for LV in non-clustered VG.

The LV locks make sense only for clustered LVs.

Properly check cluster flag and never issue cluster lock here.

There are several places in code, where it is already checked, this
patch add this check to all needed calls.

In previous code the lock behaviour was inconsistent,
for example, the pre/post callback can take lock even for local volume,
but deactivate call do not released this lock and it remains held forever.

The local LV lock request now just let run the underlying activation code
on local node, the same process like in local locking.

(Again, this is important for new mirror repair calls, here for local
mirrors but with cluster locking enabled.)