Track LLVM 14 API changes, up to 2022-01-30.
Tested with LLVM 11, LLVM 13 and LLVM's main branch at commit
8d8fce87bbd5. There are still some deprecation warnings that will need
to be sorted out, but this may be enough to turn "seawasp" green again.
Like commit e6a76002, done on master only for
Track LLVM 14 API changes.
Only done on the master branch for now to fix build farm animal seawasp
(which tests bleeeding edge PostgreSQL with bleeding edge LLVM). We can
back-patch a consolidated fix closer to LLVM 14's release, once its API
has stopped moving around.
Discussion:
https://postg
