Use write_str

Co-authored-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>

dev-tools/gen-target-info/src/main.rs

@@ -13,9 +13,7 @@ const PRELUDE: &str = r#"//! This file is generated code. Please edit the genera
 fn generate_target_mapping(f: &mut File, target_specs: &RustcTargetSpecs) -> std::io::Result<()> {
     writeln!(f, "use super::Target;")?;
     writeln!(f)?;
-    writeln!(
-        f,
-        "pub(crate) fn get(target_triple: &str) -> Option<Target> {{"
+    f.write_str("pub(crate) fn get(target_triple: &str) -> Option<Target> {"
     )?;
     writeln!(f, "    Some(match target_triple {{")?;