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

New packages: OpenEXR 3.1.5 + Imath 3.1.6
https://github.com/void-linux/void-packages/pull/40753

Description:
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Continuation of #36361. I thought maybe it's easier to split the PR by adding these as new packages first and update revdeps individually then remove old openexr/ilmbase packages.

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

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