Mark .rmeta files as /SAFESEH on x86 Windows.

Chrome links .rlibs with /WHOLEARCHIVE or -Wl,--whole-archive to prevent
the linker from discarding static initializers. This works well, except
on Windows x86, where lld complains:

  error: /safeseh: lib.rmeta is not compatible with SEH

The fix is simply to mark the .rmeta as SAFESEH aware. This is trivially
true, since the metadata file does not contain any executable code.

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1889,37 +1889,14 @@ fn add_linked_symbol_object(
         return;
     };
 
-    // NOTE(nbdd0121): MSVC will hang if the input object file contains no sections,
-    // so add an empty section.
     if file.format() == object::BinaryFormat::Coff {
+        // NOTE(nbdd0121): MSVC will hang if the input object file contains no sections,
+        // so add an empty section.
         file.add_section(Vec::new(), ".text".into(), object::SectionKind::Text);
 
         // We handle the name decoration of COFF targets in `symbol_export.rs`, so disable the
         // default mangler in `object` crate.
         file.set_mangling(object::write::Mangling::None);
-
-        // Add feature flags to the object file. On MSVC this is optional but LLD will complain if
-        // not present.
-        let mut feature = 0;
-
-        if file.architecture() == object::Architecture::I386 {
-            // Indicate that all SEH handlers are registered in .sxdata section.
-            // We don't have generate any code, so we don't need .sxdata section but LLD still
-            // expects us to set this bit (see #96498).
-            // Reference: https://docs.microsoft.com/en-us/windows/win32/debug/pe-format
-            feature |= 1;
-        }
-
-        file.add_symbol(object::write::Symbol {
-            name: "@feat.00".into(),
-            value: feature,
-            size: 0,
-            kind: object::SymbolKind::Data,
-            scope: object::SymbolScope::Compilation,
-            weak: false,
-            section: object::write::SymbolSection::Absolute,
-            flags: object::SymbolFlags::None,
-        });
     }
 
     for (sym, kind) in symbols.iter() {