pgsql: Use symbolic references for pg_language OIDs in the bootstrap da

Use symbolic references for pg_language OIDs in the bootstrap data.

This patch teaches genbki.pl to replace pg_language names by OIDs
in much the same way as it already does for pg_am names etc, and
converts pg_proc.dat to use such symbolic references in the prolang
column.

Aside from getting rid of a few more magic numbers in the initial
catalog data, this means that Gen_fmgrtab.pl no longer needs to read
pg_language.dat, since it doesn't have to know the OID of the "internal"
language; now it's just looking for the string "internal".

No need for a catversion bump, since the contents of postgres.bki
don't actually change at all.

John Naylor

Discussion: https://postgr.es/m/CAJVSVGWtUqxpfAaxS88vEGvi+jKzWZb2EStu5io-UPc4p9rSJg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/814c9019aa7b0ce3a4f19415023a256fdd717b20

Modified Files
--------------
doc/src/sgml/bki.sgml | 6 ++-
src/backend/catalog/genbki.pl | 10 ++++-
src/backend/utils/Gen_fmgrtab.pl | 7 ++-
src/backend/utils/Makefile | 8 +---
src/include/catalog/pg_proc.dat | 92 ++++++++++++++++++++--------------------
src/include/catalog/pg_proc.h | 2 +-
src/tools/msvc/Solution.pm | 4 +-
7 files changed, 66 insertions(+), 63 deletions(-)