linux: relocate PIDFD definitions to src/new

[raushan728]

Relocated the pidfd module to src/new/linux_uapi/linux/pidfd.rs to match the modern directory structure.

• Registered pidfd under the linux target in src/new.

• Updated libc-test to properly skip PIDFD_ constants on older kernels.

[tgross35]

Adding the constant is fine, though you should do = O_NONBLOCK like it is in source rather than redefining.

If you are interested in doing reorganization, though, instead of sorting could you just move all the relevant pidfd bits to a new file src/new/linux_uapi/linux/pidfd.h? Making sure things match up with https://github.com/torvalds/linux/blob/0f2acd3148e0ef42bdacbd477f90e8533f96b2ac/include/uapi/linux/pidfd.h.

[raushan728]

@tgross35 done i have relocated everything to src/new and addressed all your feedback. thanks for the guidance. plz take a look

[tgross35]

The file structure looks correct to me now, but it looks like there are still some changes that need to be dropped here

View changes since this review

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[raushan728]

@tgross35 addressed all feedback — reverted unrelated visibility/formatting changes, removed newly-added constants (only relocated existing definitions), and dropped the android skip block

[raushan728]

@rustbot ready