Set no_default_libraries: false in wasm32_emscripten target

Author: hoodmane

compiler/rustc_target/src/spec/wasm32_unknown_emscripten.rs

@@ -28,6 +28,7 @@ pub fn target() -> Target {
         linker: None,
         is_like_emscripten: true,
         panic_strategy: PanicStrategy::Unwind,
+        no_default_libraries: false,
         post_link_args,
         families: cvs!["unix", "wasm"],
         ..options