krata: begin work on guest message channel

crates/xen/xenevtchn/src/error.rs

@@ -2,11 +2,11 @@ use std::io;
 
 #[derive(thiserror::Error, Debug)]
 pub enum Error {
-    #[error("kernel error")]
+    #[error("kernel error: {0}")]
     Kernel(#[from] nix::errno::Errno),
-    #[error("io issue encountered")]
+    #[error("io issue encountered: {0}")]
     Io(#[from] io::Error),
-    #[error("failed to send event channel wake")]
+    #[error("failed to send event channel wake: {0}")]
     WakeSend(tokio::sync::broadcast::error::SendError<u32>),
 }