tdb: rework cleanup logic in tdb_runtime_check_for_robust_mutexes()

tdb: rework cleanup logic in tdb_runtime_check_for_robust_mutexes()

The cleanup logic used six goto lables, at least I'm not able to make
sane modifications to such a beast.

By using state flags that track which objects are initialized and need
cleanup, we get rid of the goto labels. It comes at a cost though: you
have to be careful to correctly set the cleanup flags.

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Uri Simchoni <uri@samba.org>