There's a closed pull request on the void-packages repository

postfix: add build options
https://github.com/void-linux/void-packages/pull/31230

Description:
Enable build to be more modular by making most of the dependencies
optional. Specifically, mysql, pgsql, sqlite, ldap, sasl and pcre are
not strictly required and are all optional dependencies.

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#### General
- [ ] This is a new package and it conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements)

#### Have the results of the proposed changes been tested?
- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [ ] I generally don't use the affected packages but briefly tested this PR

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