https://archlinux.org/todo/icu-76/

Fixes #6

Fixes: abc62f6e

Fixes ccb8993d

0755 is "normal" but the change is unnecessary.

As recommended by upstream.

Fixes: #2

Also make `/var/lib/postgres`     mode `0700` and
          `/var/lib/postgres/data mode `0755`.

Fixes: #1

- Use its depends on the top level, simplifying makedepends
- Will make it easier to port to meson + _pick later

Suggest the C.UTF-8 locale that's shipped by default instead of
en_US.UTF-8 which requires generating it before use.

Another advantage of C.UTF-8 is that it won't trigger the
`collation version mismatch` warning after glibc or icu updates since
its `collversion` is NULL.

Fixes #3

Additionally, replace `su -` with `su -l` as recommended by the su(1)
man page.

The filesystem package recently changed the path for the root user.

Remove redundant versioned deps and add build fix for libxml2 2.12. [1]

[1] https://www.postgresql.org/message-id/CACpMh%2BDMZVHM%2BiDSyqdcpK8sr7jd_HxxLJRNvGTzcLBE0W07QA%40mail.gmail.com

See: https://github.com/postgres/postgres/commit/efa8f606402c3d7ca361932418cbcc2600b6c059

Closes #4

Pass them through git apply (on top of REL_15_4), commit and
format-patch. This also makes forward-porting easier by leveraging git
rebase.

PostgreSQL JIT has not been ported to LLVM 16 yet; use LLVM 14 for now.