rust: use std::ffi instead of std::os::raw

This is allowed since Rust 1.64.0.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rust/qemu-api/src/memory.rs

@@ -5,9 +5,8 @@
 //! Bindings for `MemoryRegion`, `MemoryRegionOps` and `MemTxAttrs`
 
 use std::{
-    ffi::{CStr, CString},
+    ffi::{c_uint, c_void, CStr, CString},
     marker::PhantomData,
-    os::raw::{c_uint, c_void},
 };
 
 pub use bindings::{hwaddr, MemTxAttrs};