WIP: Add support for `mbind`, `get_mempolicy` and `set_mempolicy`

[krh]

This adds support for the mbind, set_mempolicy and get_mempolicy NUMA syscalls. The get_mempolicy syscall has a few different modes of operation, depending on the flags, which is demultiplexed into get_mempolicy_node and get_mempolicy_next_node for now. There's a couple of other modes that writes into the variable length bit array, which aren't implemented for now.

[krh]

Pushed a new version: removed the emacs backup files, fixed cargo fmt and warnings about unused imports. Remaining errors look like they're all from missing the new symbols in linux-raw-sys.

[krh]

This one: https://github.com/sunfishcode/linux-raw-sys/pull/96

[sunfishcode]

If you'd like this PR to be included in the rustix 0.38 series, please use linux-raw-sys 0.4.x. I've now released 0.4.12 with https://github.com/sunfishcode/linux-raw-sys/pull/96. Another option is to open this PR in the 1.0-staging branch.

[krh]

If you'd like this PR to be included in the rustix 0.38 series, please use linux-raw-sys 0.4.x. I've now released 0.4.12 with sunfishcode/linux-raw-sys#96. Another option is to open this PR in the 1.0-staging branch.

Oh, ok, thanks, I'll target 0.4.12 then.