refactor: derive Clone, Copy for SnapshotType

Passing this enough around by reference was making for awkward
dereferencing when comparing.

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

src/vmm/src/persist.rs

@@ -200,7 +200,7 @@ pub fn create_snapshot(
         version_map,
     )?;
 
-    snapshot_memory_to_file(vmm, &params.mem_file_path, &params.snapshot_type)?;
+    snapshot_memory_to_file(vmm, &params.mem_file_path, params.snapshot_type)?;
 
     Ok(())
 }
@@ -234,7 +234,7 @@ fn snapshot_state_to_file(
 fn snapshot_memory_to_file(
     vmm: &Vmm,
     mem_file_path: &Path,
-    snapshot_type: &SnapshotType,
+    snapshot_type: SnapshotType,
 ) -> Result<(), CreateSnapshotError> {
     use self::CreateSnapshotError::*;
     let mut file = OpenOptions::new()

src/vmm/src/vmm_config/snapshot.rs

@@ -11,7 +11,7 @@ use serde::{Deserialize, Serialize};
 
 /// The snapshot type options that are available when
 /// creating a new snapshot.
-#[derive(Debug, Default, PartialEq, Eq, Deserialize, Serialize)]
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Deserialize, Serialize)]
 pub enum SnapshotType {
     /// Diff snapshot.
     Diff,