This fixes https://github.com/postmarketOS/binary-package-repo/issues/1
GCC generates hardlinks between files `A` and `B` in its `make install` step. The problem is, that `tar` randomly packages `A` as full binary, and links `B` to `A`, or the other way around! I was able to reproduce this issue consistently when re-building `gcc-aarch64` on Travis CI (interestingly, this did not appear for `gcc-armhf`).
The fix is, to delete `B` and create a symlink `B` that points to `A` instead.