[pbs-devel] [PATCH backup 12/13] datastore: simplify let-else block with ? operator

[Maximiliano Sandoval]

Fixes the question_mark clippy lint:

```
warning: this `let...else` may be rewritten with the `?` operator
   --> pbs-datastore/src/datastore.rs:101:5
    |
101 | /     let Some(ref device_uuid) = config.backing_device else {
102 | |         return None;
103 | |     };
    | |______^ help: replace it with: `let ref device_uuid = config.backing_device?;`
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#question_mark
    = note: `#[warn(clippy::question_mark)]` on by default
```

Signed-off-by: Maximiliano Sandoval <m.sandoval at proxmox.com>
---
 pbs-datastore/src/datastore.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/pbs-datastore/src/datastore.rs b/pbs-datastore/src/datastore.rs
index 24d9eab2e..cf55befaa 100644
--- a/pbs-datastore/src/datastore.rs
+++ b/pbs-datastore/src/datastore.rs
@@ -98,9 +98,7 @@ fn is_datastore_mounted_at(store_mount_point: String, device_uuid: &str) -> bool
 }
 
 pub fn get_datastore_mount_status(config: &DataStoreConfig) -> Option<bool> {
-    let Some(ref device_uuid) = config.backing_device else {
-        return None;
-    };
+    let device_uuid = config.backing_device.as_ref()?;
     Some(is_datastore_mounted_at(config.absolute_path(), device_uuid))
 }
 
-- 
2.39.5