Trivial adjustments in preparation for bootstrap data conversion.

Trivial adjustments in preparation for bootstrap data conversion.

Rationalize a couple of macro names:
* In catalog/pg_init_privs.h, rename Anum_pg_init_privs_privs to
  Anum_pg_init_privs_initprivs to match the column's actual name.
* In ecpg, rename ZPBITOID to BITOID to match catalog/pg_type.h.
This reduces reader confusion, and will allow us to generate these
macros automatically in future.

In catalog/pg_tablespace.h, fix the ordering of related DATA and
#define lines to agree with how it's done elsewhere.  This has no
impact today, but simplifies life for the bootstrap data conversion
scripts.

John Naylor

Discussion: https://postgr.es/m/CAJVSVGXnLH=BSo0x-aA818f=MyQqGS5nM-GDCWAMdnvQJTRC1A@mail.gmail.com