tools: parse_objset_stat: drop the unecessary 'objset-' from the log

'objset_id' already contains that, so the error was
"could not parse 'objset-objset-0xFFFF' stat file"

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

src/tools/disks/zfs.rs

@@ -124,7 +124,7 @@ fn parse_objset_stat(pool: &str, objset_id: &str) -> Result<(String, BlockDevSta
 
     let text = match proxmox_sys::fs::file_read_optional_string(&path)? {
         Some(text) => text,
-        None => bail!("could not parse 'objset-{}' stat file", objset_id),
+        None => bail!("could not parse '{}' stat file", objset_id),
     };
 
     let mut dataset_name = String::new();