Jacob G-W 841b54f5e3 std: add SbrkAllocator and use it for Plan 9
Implements issue #6451.
This was needed to support allocation on Plan 9 and now other operating
systems like DOS can also use it.

It is a modified version of the WasmAllocator since wasm also uses a
sbrk-esque allocation system.

This commit also adds the necessary system bits for sbrk to work on plan 9.
2023-08-02 17:39:52 -04:00
..