Binary packages are rebuilding. If your kernel is not rebuilt yet, and
you don't want to build it yourself, just checkout the previous
pmbootstrap commit.
This commit also changes the arch from the postmarketOS kernels from
"all" to the ones where we actually have a kernel config.
Fixes#1229.
Fixes#1227.
This also updates the hash in linux-postmarketos-mainline, because the
hash changed upstream (they updated their git version server-side?).