Rollup merge of #132261 - ChrisCho-H:refactor/cleaner-check-none, r=compiler-errors

refactor: cleaner check to return None

It's very nit change. Refactor to shorten verbose check when returning None for `backend_feature_name`.

Author: workingjubilee

Diff for: compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -698,12 +698,9 @@ fn backend_feature_name<'a>(sess: &Session, s: &'a str) -> Option<&'a str> {
     let feature = s
         .strip_prefix(&['+', '-'][..])
         .unwrap_or_else(|| sess.dcx().emit_fatal(InvalidTargetFeaturePrefix { feature: s }));
-    if s.is_empty() {
-        return None;
-    }
     // Rustc-specific feature requests like `+crt-static` or `-crt-static`
     // are not passed down to LLVM.
-    if RUSTC_SPECIFIC_FEATURES.contains(&feature) {
+    if s.is_empty() || RUSTC_SPECIFIC_FEATURES.contains(&feature) {
         return None;
     }
     Some(feature)