feat: pci passthrough (#114)

* feat: pci passthrough

* feat: guest device management

* feat: addons mounting and kernel modules support

* feat: more pci work

* fix: kernel build squashfs fixes

* fix: e820entry should be available on all platforms

crates/xen/xenclient/examples/boot.rs

@@ -27,6 +27,7 @@ async fn main() -> Result<()> {
         disks: vec![],
         channels: vec![],
         vifs: vec![],
+        pcis: vec![],
         filesystems: vec![],
         extra_keys: vec![],
         extra_rw_paths: vec![],