dbermond [1] filed an orphan request for mips64el-linux-gnu-linux-api- headers [2]:

Package is out-of-date for a long period of time (not flagged, but it's out-of-date in relation to upstream releases since a long time). Last maintainer login on the AUR web interface was almost two years ago, so it seems really abandoned.

[1] https://aur.archlinux.org/account/dbermond/ [2] https://aur.archlinux.org/pkgbase/mips64el-linux-gnu-linux-api-headers/