HvpCreateHiveFreeCellList returns a NTSTATUS code yet the way the code path checks
checks for failure is just wrong. This was spotted whilst working on #4571 PR.
In principle there should be different get-cell routines, depending
on the type of the hive (given by the OperationType parameter of
HvInitialize): for flat hives, memory-mapped hives, etc.
For now in ReactOS we only support a restricted subset of these,
therefore we are still happy with a single get-cell callback...
This may change in the future.
