Stripping fails when using qemu-user-static (aarch64 on x86)

[orowith2os]

Checklist

• [X] I agree to follow the Code of Conduct that this project adheres to.
• [X] I have searched the issue tracker for a bug that matches the one I want to file, without success.

flatpak-builder version

1.3.1

Flatpak version

1.15.4

How to reproduce

1. Make a multi-arch (aarch64 and x86_64) Flatpak manifest that sets strip to true in build-options.
2. Build a Flatpak application or extension on an x86 host in an aarch64 environment: flatpak-builder --user --force-clean build-dir org.freedesktop.Platform.VulkanLayer.gamescope.yml --install --arch=aarch64
3. Watch as stripping fails.

To test this out, use the manifest in https://github.com/flathub/flathub/pull/4329.

Expected Behavior

Stripping works normally, as it would when building on x86 and aarch64 natively.

Actual Behavior

Stripping fails when building a Flatpak not on the native arch.

Installing symlink pointing to libevdev.so.2 to /usr/lib/extensions/vulkan/gamescope/lib/libevdev.so
stripping: files/lib/libevdev.so.2.3.0
strip: Unable to recognise the format of the input file `/var/home/oro/org.freedesktop.Platform.VulkanLayer.gamescope/.flatpak-builder/rofiles/rofiles-ebVMtV/files/lib/libevdev.so.2.3.0'
Error: module libevdev: Child process exited with code 1