Re: Add 64-bit XIDs into PostgreSQL 15

Hi,

With these patches, it seems that we don’t need to handle wraparound in 
GetNextLocalTransactionId() too, as LocalTransactionId is unit64 now.

```
LocalTransactionId
GetNextLocalTransactionId(void)
{
    LocalTransactionId result;

    /* loop to avoid returning InvalidLocalTransactionId at wraparound */
    do
    {
        result = nextLocalTransactionId++;
    } while (!LocalTransactionIdIsValid(result));

    return result;
}
```