[WIP] initoverlayfs: Add initial initoverlayfs support

This patch adds the option to use initoverlayfs project with
Signed-off-by: Douglas Schilling Landgraf <[email protected]>

rust/src/cliwrap/kernel_install.rs

@@ -64,6 +64,14 @@ fn redo_systemctl_wrap() -> Result<()> {
     Ok(())
 }
 
+#[context("Running initoverlayfs")]
+fn run_initoverlayfs() -> Result<()> {
+    const INITOVERLAY_INSTALL_CMD: &str = "initoverlayfs-install";
+
+    let _ = cliutil::exec_real_binary(INITOVERLAY_INSTALL_CMD, &empty_argv);
+    Ok(())
+}
+
 #[context("Running dracut")]
 fn run_dracut(kernel_dir: &str) -> Result<()> {
     let root_fs = Utf8Dir::open_ambient_dir("/", cap_std::ambient_authority())?;
@@ -108,5 +116,10 @@ fn run_dracut(kernel_dir: &str) -> Result<()> {
         &root_fs,
         (Utf8Path::new("lib/modules").join(kernel_dir)).join("initramfs.img"),
     )?;
+
+    if let Err(error) = run_initoverlayfs() {
+        return Err(anyhow!("Failed to execute initoverlayfs: {}", error));
+    }
+
     Ok(())
 }