The Linux kernel doesn't allow for anonymous or pseudonymous contributions. It does allow for organizations to contribute on behalf of people working for or through them.
If Asahi wants to submit this upstream, then they and Marcan can put their name to it. Hector Martin or another person at Asahi would be the name on the git commit, and they would almost certainly be taken at their word that there is no concern with the merge around Lina's identity.
It's not like other commits which are done from clean room re-implementations are requiring a background check on the person submitting it.