This change brings the /zip/... read-only filesystem into performance
parity with the native Linux filesystem which doesn't use compression
therefore, imagine how much faster this could be with bloom filtering
rather than simple binary search, and if we used zstd instead of zlib
This change improves the dirstream library in a lot of respects,
especially for /zip/... files. Also turn off MAP_STACK on Aarch64
because Qemu seems to implement it differently than Linux and it's
probably responsible for a lot of mysterious crashes.
This way complex runtime features (e.g. ftrace, symbol tables) can
always yoink zipos support. This is important now that apelink.com
automates embedding symbol tables for multiple cpus.
