Clean up bits for crucible in propolis-standalone

bin/propolis-standalone/src/config.rs

@@ -45,10 +45,7 @@ pub fn block_backend(
             let creg = ChildRegister::new(&be, Some(path.to_string()));
             (be, creg)
         }
-        #[cfg(feature = "crucible")]
         "crucible" => create_crucible_backend(log, be),
-        #[cfg(not(feature = "crucible"))]
-        "crucible" => panic!("crucible device specified in VM config, but propolis-standalone was not built with crucible support. rebuild propolis-standalone with the `crucible` feature enabled, or remove all crucible devices from your VM config"),
         _ => {
             panic!("unrecognized block dev type {}!", be.bdtype);
         }
@@ -202,3 +199,14 @@ fn create_crucible_backend(
         ChildRegister::new(&be, Some(be.get_uuid().unwrap().to_string()));
     (be, creg)
 }
+
+#[cfg(not(feature = "crucible"))]
+fn create_crucible_backend(
+    _log: &slog::Logger,
+    _be: &propolis_standalone_config::BlockDevice,
+) -> (Arc<dyn block::Backend>, ChildRegister) {
+    panic!(
+        "Rebuild propolis-standalone with 'crucible' feature enabled in \
+           order to use the crucible block backend"
+    );
+}

xtask/src/task_clippy.rs

@@ -39,6 +39,10 @@ pub(crate) fn cmd_clippy(strict: bool) -> Result<()> {
     failed |=
         run_clippy(&["-p", "propolis-server", "--features", "mock-only"])?;
 
+    // Check standalone with crucible enabled
+    failed |=
+        run_clippy(&["-p", "propolis-standalone", "--features", "crucible"])?;
+
     if failed {
         bail!("Clippy failures detected")
     }