Remove runtime dependency on libc

[XrXr]

I think one fewer runtime dependency is good. How about it?

• capstone-rs: Remove runtime depdendency on libc

  • C types under core::ffi have been stable since 1.64.0
  • core::ffi::CStr was already in use, so we can use it instead
    of libc::strlen.

  Since libcore has everything we need, remove the dependency on the libc
  crate at runtime.

• capstone-sys: Remove runtime dependency on libc
  C types under core::ffi have been stable since 1.64.0, below MSRV.

[jiegec]

Good idea!

[tmfink]

Thanks for the PR! I'll take a closer look.

I think you mean to say that you removed the "compile-time" dependency on the libc Rust crate.
It looks like this does not remove libc dependency from the workspace's Cargo.lock because of the criterion -> is-terminal -> libc dependency chain, but this is still a good improvement since it could still speed up builds a little for those depending on the our library.