posix/iqueue: Creating queue pairs between processes for low latency small message transport

[yfguo]

Pull Request Description

Description WIP. PR need some clean up as well. But the functionality is ready and performance analysis is done.

Author Checklist

• [ ] Provide Description Particularly focus on why, not what. Reference background, issues, test failures, xfail entries, etc.
• [ ] Commits Follow Good Practice Commits are self-contained and do not do two things at once. Commit message is of the form: module: short description Commit message explains what's in the commit.
• [ ] Passes All Tests Whitespace checker. Warnings test. Additional tests via comments.
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