Do not import libc on windows

cranelift-simplejit/src/backend.rs

@@ -8,6 +8,7 @@ use cranelift_module::{
     Backend, DataContext, DataDescription, Init, Linkage, ModuleNamespace, ModuleResult,
 };
 use cranelift_native;
+#[cfg(not(windows))]
 use libc;
 use std::collections::HashMap;
 use std::ffi::CString;

cranelift-simplejit/src/memory.rs

@@ -2,6 +2,7 @@
 use errno;
 
 #[cfg(not(feature = "selinux-fix"))]
+#[cfg(not(windows))]
 use libc;
 
 #[cfg(feature = "selinux-fix")]