Removing built-in support for sqlite3

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

NetBSD comes with sqlite3 in the base system. It mostly imported for
supporting a heimdal feature (since disabled) and for apropos(1).

The version is not kept up-to-date (NetBSD 10 comes with 3.26, pkgsrc
has 3.45). Some software in pkgsrc requires features that are not
enabled in the base system version.

I'd like to remove builtin support for sqlite3 from pkgsrc (basically,
cvs rm databases/sqlite3/builtin.mk).

- We'll know what features the used sqlite3 will have, by depending on a
  (pkgsrc) version that has that feature enabled by default.

- We avoid linking against both version in the same executable (if one
  dependency is happy with the older version, but something else wants
  a newer one and pulls in the pkgsrc version).

- The sqlite3 package itself is small (32MB) and pulls in no other
  runtime dependencies.

Comments?
 Thomas