Update uefi requirement from 0.15 to 0.21 in /kernel

[dependabot]

Updates the requirements on uefi to permit the latest version.

Changelog

Sourced from uefi's changelog.

uefi - 0.21.0 (2023-05-15)

Added

• There is a new fs module that provides a high-level API for file-system access. The API is close to the std::fs module. The module also provides a Path and a PathBuf abstraction that is similar to the ones from std::path. However, they are adapted for UEFI.
• Multiple convenience methods for CString16 and CStr16, including:
  • CStr16::as_slice()
  • CStr16::num_chars()
  • CStr16::is_empty()
  • CString16::new()
  • CString16::is_empty()
  • CString16::num_chars()
  • CString16::replace_char()
  • CString16::push()
  • CString16::push_str()
  • From<&CStr16> for CString16
  • From<&CStr16> for String
  • From<&CString16> for String
• Added RuntimeServices::get_variable_boxed (requires the alloc feature).
• Added CStr16::as_bytes
• Added AsRef<[u8]> and Borrow<[u8]> for Cstr8 and CStr16.
• Added LoadedImageDevicePath protocol.
• Added FileAttribute::is_directory(&self) and FileAttribute::is_regular_file(&self)
• Added LoadedImage::code_type() and LoadedImage::data_type()
• Allocator will now use the memory type of the running UEFI binary:
  • MemoryType::LOADER_DATA for UEFI applications
  • MemoryType::BOOT_SERVICES_DATA for UEFI boot drivers
  • MemoryType::RUNTIME_SERVICES_DATA for UEFI runtime drivers

Changed

• The global_allocator module has been renamed to allocator, and is now available regardless of whether the global_allocator feature is enabled. The global_allocator feature now only controls whether allocator::Allocator is set as Rust's global allocator.
• Error::new and Error::from now panic if the status is SUCCESS.
• Image::get_image_file_system now returns a fs::FileSystem instead of the protocol.
• CString16::default now always contains a null character.
• Conversion from Status to Result has been reworked. The into_with, into_with_val, and into_with_err methods have been removed from Status. impl From<Status> for Result has also been removed. A new StatusExt trait has been added that provides conversion methods to replace the ones that have been removed. StatusExt has been added to the prelude.
• The Guid struct and guid! macro implementations have been replaced with re-exports from the uguid crate. The from_values

... (truncated)

Commits

• 0965660 chore: Release
• bb2f56b uefi: Bump uefi-macros version
• 148d438 chore: Release
• e6803d7 allocator: Use appropriate memory types
• 9dbdfe9 loaded_image: Provide getters for memory types
• 816d39c Merge pull request #803 from nicholasbishop/bishop-disable-debug-supp-aarch64
• 94bd9aa Disable multi-processor test on aarch64
• 182bda4 Disable DebugSupport protocol test on aarch64
• 2f182bf Merge pull request #802 from nicholasbishop/bishop-drop-dep
• 37c953e uefi-raw: Drop dep on uefi-macros
• Additional commits viewable in compare view

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[dependabot]

Superseded by #314.