Update list of platforms vulnerable to TOCTOU in remove_dir_all

[emilyalbini]

Neither platform can reasonably protect against TOCTOU in remove_dir_all:

• VxWorks doesn't always have the required API (depending on how it's built), and its security model prevents untrusted processes from existing.
• QNX itself is broken and prevents the use of openat(): in QNX 7.1, O_NOFOLLOW is straight up ignored, and in QNX 8.0 openat() works but there is a TOCTOU in the kernel itself.

[rustbot]

r? @Mark-Simulacrum

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[Noratrieb]

@bors r+ rollup

[rust-bors]

📌 Commit 23a860e has been approved by Noratrieb

It is now in the queue for this repository.

[JonathanBrouwer]

@bors r=noratrieb
Bors does not want to put this in a rollup for some reason, maybe this helps?

[rust-bors]

📌 Commit 23a860e has been approved by noratrieb

It is now in the queue for this repository.

[JonathanBrouwer]

@bors r-

[rust-bors]

This pull request was unapproved.

View changes since this unapproval

[JonathanBrouwer]

@bors r=noratrieb

[rust-bors]

📌 Commit 23a860e has been approved by noratrieb

It is now in the queue for this repository.

[JonathanBrouwer]

Hmmm it's still saying
Merge of #156702 failed with error: NotFound