Stabilize Wasm phase 4 & 5 proposals

Author: daxpedda

Diff for: compiler/rustc_codegen_ssa/src/target_features.rs

@@ -282,14 +282,15 @@ const RISCV_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
 const WASM_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     // tidy-alphabetical-start
     ("atomics", Some(sym::wasm_target_feature)),
-    ("bulk-memory", Some(sym::wasm_target_feature)),
+    ("bulk-memory", None),
     ("exception-handling", Some(sym::wasm_target_feature)),
+    ("extended-const", None),
     ("multivalue", Some(sym::wasm_target_feature)),
-    ("mutable-globals", Some(sym::wasm_target_feature)),
-    ("nontrapping-fptoint", Some(sym::wasm_target_feature)),
+    ("mutable-globals", None),
+    ("nontrapping-fptoint", None),
     ("reference-types", Some(sym::wasm_target_feature)),
     ("relaxed-simd", Some(sym::wasm_target_feature)),
-    ("sign-ext", Some(sym::wasm_target_feature)),
+    ("sign-ext", None),
     ("simd128", None),
     // tidy-alphabetical-end
 ];