graphics/openexr: update to v3.2.1

ChangeLog: https://github.com/AcademySoftwareFoundation/openexr/blob/v3.2.1/CHANGES.md#version-321-september-27-2023

with one additional patch to change deflate_LIBRARIES to
deflate_LINK_LIBRARIES in the cmake stuff in order to unbreak
the build.

Reported upstream: https://github.com/AcademySoftwareFoundation/openexr/issues/1571

Upstream intended to release v3.2.2 on short notice, but the efforts
appear to have stalled, so ship 3.2.1 with our local fix.