Bug#35256375 node crash with signal 6000

Fix backport to 7.5 + 7.6

Ndb data node transaction controller (TC) components reuse
transaction management objects.
In some cases control state was not re-initialised resulting
in incorrect logic for subsequent transactions.
Specifically, where a transaction has pending deferred triggers
and does not commit, a subsequent transaction may :
 - Waste resources checking for deferred triggers
   - Cause a crash if it has no committable operations

The state initialisation is fixed, and a test covering this
scenario is added.

Change-Id: I6da9f6a70fa3de7d7d799aebca84b3cab0272044

Author: frazerclement