winsys/amdgpu: Make KMS handles valid for original DRM file descriptor
These changes fix https://bugs.freedesktop.org/110903 . They replace https://patchwork.freedesktop.org/series/62663/ and don't require any libdrm_amdgpu
API changes anymore.
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These changes fix https://bugs.freedesktop.org/110903 . They replace https://patchwork.freedesktop.org/series/62663/ and don't require any libdrm_amdgpu
API changes anymore.