style: Remove unnecessary explicit return statements

Use implicit return expressions instead of explicit `return` statements
for the final expression in functions, following Rust conventions.

Assisted-by: Claude Code (Sonnet 4.5)
Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

crates/lib/src/bootc_composefs/boot.rs

@@ -178,7 +178,7 @@ pub fn get_sysroot_parent_dev() -> Result<String> {
         anyhow::bail!("Could not find parent device for mountpoint /sysroot");
     };
 
-    return Ok(parent);
+    Ok(parent)
 }
 
 pub fn type1_entry_conf_file_name(sort_key: impl std::fmt::Display) -> String {
@@ -211,7 +211,7 @@ fn compute_boot_digest(
 
     let digest: &[u8] = &hasher.finish().context("Finishing digest")?;
 
-    return Ok(hex::encode(digest));
+    Ok(hex::encode(digest))
 }
 
 /// Given the SHA256 sum of current VMlinuz + Initrd combo, find boot entry with the same SHA256Sum

crates/lib/src/bootc_composefs/status.rs

@@ -126,7 +126,7 @@ pub(crate) fn get_sorted_type1_boot_entries(
 
     all_configs.sort_by(|a, b| if ascending { a.cmp(b) } else { b.cmp(a) });
 
-    return Ok(all_configs);
+    Ok(all_configs)
 }
 
 /// imgref = transport:image_name
@@ -244,7 +244,7 @@ async fn boot_entry_from_composefs_deployment(
         soft_reboot_capable: false,
     };
 
-    return Ok(e);
+    Ok(e)
 }
 
 #[context("Getting composefs deployment status")]