[proposal] binfmt_misc: pass binfmt_misc flags to the interpreter

commit 2347961b11d4079deace3c81dceed460c08a8fc1

I would like to propose this commit from 5.12 for stable, or rather, ask whether it’s a candidate and leave the exact picking/backporting to the experts (if it has other commits as prerequisites and/or later fixups).

This is because qemu-user needs it, and it arrived just too late for the current Debian LTS kernel (5.10), and qemu-user in Debian until yesterday had a workaround, but now doesn’t because it’s in the stable kernel (6.1), so qemu-user-static cannot be just used as-is on Debian LTS any more.

I’d like it to be applied to 5.10 (obviously), but perhaps others would appreciate more broad coverage.

Thanks in advance, //mirabilos