feat(vdso): add vDSO support

[muou000]

Description

A clear and concise description of what this PR does and what changes it makes.

Type of Change

Please check the applicable options:

• Bug fix (fixes an issue)
• New feature (adds functionality)
• Documentation update (documentation only)
• Code refactoring (code improvements that don't change functionality)
• Performance improvement
• Test related
• Other (please describe)

Related Issue

Related Issue (if any): #(issue number)

Changes

Detailed description of the changes made in this PR:

• Change the Cargo.toml to import starry-vdso.
• Change api/src/lib.rs to initialize vDSO and cntvct register in aarch64.
• Change signalfd.rs because of running cargo fmt.
• Change Elfloader.load to load vDSO data.
• Implemented load_vdso_data and related functions.

Testing

Describe how you tested these changes:

• Passed clippy checks
• Formatted code (using cargo fmt)
• Tested related functionality
• Updated relevant documentation (if applicable)

Checklist

Before submitting the PR, please ensure:

• Code follows the project's code style
• Passed cargo clippy checks
• Code formatted with cargo fmt
• Commit messages follow Conventional Commits specification
• PR is as small as possible for easier review
• Updated relevant documentation (if applicable)

Additional Context

Add any other context about this PR here.

Need update starry-signal version.

[Copilot]

Pull request overview

This PR adds vDSO (virtual Dynamic Shared Object) support to Starry OS, enabling faster system calls by providing a user-space accessible shared memory region with kernel data. The implementation integrates with the ELF loader to map vDSO pages into user address spaces and provides platform-specific initialization for aarch64 timer access.

Key changes:

• Adds new vDSO module with ELF parsing and memory mapping logic for vDSO and VVAR pages
• Integrates vDSO loading into the ELF loader pipeline during process creation
• Initializes vDSO data structures and enables timer counter access on aarch64

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
core/src/vdso.rs	New module implementing vDSO loading, ELF parsing, memory mapping, and VVAR region setup
core/src/mm.rs	Integrates vDSO loading into ELF loader after auxv generation
core/src/lib.rs	Exports the new vdso module
core/Cargo.toml	Adds starry-vdso dependency
api/src/lib.rs	Initializes vDSO data and enables aarch64 timer access, registers vDSO update callback
api/Cargo.toml	Adds starry-vdso dependency
api/src/syscall/fs/signalfd.rs	Code formatting changes (import reordering and whitespace cleanup)
Cargo.toml	Adds starry-vdso workspace dependency
Cargo.lock	Dependency lock file updates for new starry-vdso package and its transitive dependencies

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[AsakuraMizu]

I'm going to give some suggestions on https://github.com/Starry-OS/starry-vdso first.