[Debian-on-mobile-maintainers] Bug#1016534: Bug #1016534: osk-sdl: "failed to open iris" cannot use it

[Benjamin Moody]

I noticed this too, although on my system (Intel HD Graphics 5300) it
seems to work with or without iris_dri.so.  However, I also needed to
patch SDL, because SDL's hardcoded pixel format (DRM_FORMAT_ARGB8888)
is not supported.

I also noticed that it would be better to use 'dri_inst' here instead
of 'copy_exec'; on amd64 just as on arm64, there are many *_dri.so
files that are duplicates (hard links, actually.)