Re: pgsql: Increase width of RelFileNumbers from 32 bits to 56 bits.

This seems to be breaking cfbot:
https://cirrus-ci.com/github/postgresql-cfbot/postgresql

For example:
https://cirrus-ci.com/task/6720256776339456

Some other minor issues:

thais is only used during

=> this

+ elog(ERROR, "unexpected relnumber " UINT64_FORMAT "that is bigger than nextRelFileNumber " UINT64_FORMAT,

=> there should be a space before "that".

+ "tli %u; prev tli %u; fpw %s; xid %u:%u; relfilenumber " UINT64_FORMAT ";oid %u; "

=> and a space before "oid"

+ * Parse relfilenumber value for an option. If the parsing is successful,
+ * returns; if parsing fails, returns false.

returns *true;