Remove unneeded extern crate, macro_use, and tidy uses.

fuzz/fuzz_targets/compile.rs

@@ -1,13 +1,13 @@
 #![no_main]
 
-#[macro_use]
-extern crate libfuzzer_sys;
 extern crate alloc;
 extern crate core;
+extern crate libfuzzer_sys;
 
 use alloc::rc::Rc;
 use core::cell::RefCell;
 use cranelift_codegen::settings;
+use libfuzzer_sys::fuzz_target;
 use std::collections::HashMap;
 use wasmparser::validate;
 use wasmtime_jit::{CompilationStrategy, CompiledModule, Compiler, NullResolver};