misc: fix some clippy errors

common/src/elf.rs

@@ -4,5 +4,5 @@ use object::{Endianness, build::elf::Builder};
 
 #[allow(clippy::missing_const_for_fn)]
 pub fn write() {
-    let builder = Builder::new(Endianness::Little, false);
+    let _builder = Builder::new(Endianness::Little, false);
 }

emulator/src/emulator/misc/rpc.rs

@@ -180,10 +180,10 @@ impl Drop for RpcClient {
     fn drop(&mut self) {
         self.stop();
 
-        if let Some(handle) = self.thread_handle.take() {
-            if let Some(handle) = Arc::into_inner(handle) {
-                let _ = handle.join();
-            }
+        if let Some(handle) = self.thread_handle.take()
+            && let Some(handle) = Arc::into_inner(handle)
+        {
+            let _ = handle.join();
         }
     }
 }

emulator/src/emulator/system/emulator.rs

@@ -110,6 +110,7 @@ pub fn run_emulator(
                             );
                         });
                 }
+                #[expect(unused_assignments)]
                 Command::Interrupt(_interrupt) => {
                     update = true;
 

emulator/src/emulator/system/processor/mod.rs

@@ -19,6 +19,7 @@ pub struct Processor {
     pub dustbin: u32,
 }
 
+#[expect(dead_code)]
 fn log(message: &str) {
     println!("\x1b[32mINFO:\x1b[0m {message}");
 }