Remove patched libc crate

Cargo.toml

@@ -115,7 +115,5 @@ rustc-std-workspace-core = { path = 'library/rustc-std-workspace-core' }
 rustc-std-workspace-alloc = { path = 'library/rustc-std-workspace-alloc' }
 rustc-std-workspace-std = { path = 'library/rustc-std-workspace-std' }
 
-libc = { git = "https://gitlab.redox-os.org/redox-os/liblibc.git", branch = "rust-2022-03-18" }
-
 [patch."https://github.com/rust-lang/rust-clippy"]
 clippy_lints = { path = "src/tools/clippy/clippy_lints" }