We've already worked around failing stat() calls in the installer by
running it in qemu-user. Turns out on some systems this workaround is
also needed to run `wlib', the archiver of the Open Watcom toolchain.
This issue manifested itself in broken VirtualBox builds due to
/build/virtualbox/out/linux.amd64/dbgopt/obj/VBoxPcBios32/pci32.obj
not being found by `wlib'.
We now just wrap all binaries in qemu-user to avoid this.
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