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

combine rust and cargo templates
https://github.com/void-linux/void-packages/pull/36426

Description:
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@q66, wanted to get your opinion on these changes before I go further. I did my best to fold the `cargo{,-bootstrap}` templates into the `rust{,-bootstrap}` ones, preserving all patches and fixes. Tested successfully with a cross build x86_64 to aarch64. If this looks fine, I can continute working on doing some cleanups and update to 1.59 (although there is a PR for that already).

#### Testing the changes
- I tested the changes in this PR: **YES**

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[ci skip]