Non-Linux/Hurd Debian fixes
This MR brings some changes to ease the build of libsdl3 on the Hurd (and in general on non-Linux architectures).
It will not make libsdl3 build completely on the Hurd: for that there were recent changes needed upstream:
-
https://github.com/libsdl-org/SDL/pull/13702
- backported in the
release-3.2.xbranch, will be in the next 3.2.22
- backported in the
- https://github.com/libsdl-org/SDL/pull/13711
That said, the changes here should be correct, so merging them for the 3.2 series (and merging them for the 3.3 snapshot currently in experimental) will reduce the changes needed to make libsdl3 build on the Hurd. If needed/wanted, I can provide in a followup MR the backported patches for 3.2.