wasm32: Add --no-demangle option

LLD supports only C++ demangle, so disable it.

targets/wasm.json

@@ -15,6 +15,7 @@
 		"--no-threads",
 		"--stack-first",
 		"--export-all",
+		"--no-demangle",
 		"{root}/lib/wasi-libc/sysroot/lib/wasm32-wasi/libc.a"
 	],
 	"emulator":      ["node", "targets/wasm_exec.js"]