aout: destroy awn_cb_wrapper

Embind found a leaked C++ instance awn_cb_wrapper <0x13965e0>.
We'll free it automatically in this case, but this functionality is not reliable across various environments.
Make sure to invoke .delete() manually once you're done with the instance instead.
Originally allocated
    at emval_allocator_1 (eval at craftEmvalAllocator (https://192.168.1.81:8443/test/update/experimental.js:1:1), <anonymous>:7:11)
    at __emval_new (https://192.168.1.81:8443/test/update/experimental.js:9924:14)
    at (anonymous namespace)::Open(vlc_object_t*) (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[3020]:0x10750f)
    at generic_start (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[24286]:0xe38cca)
    at vlc_module_load (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[24284]:0xe38b57)
    at module_need (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[24285]:0xe38c4a)
    at aout_New (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[25045]:0xe85760)
    at input_resource_GetAout (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[24924]:0xe7d602)
    at vlc_player_aout_Init (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[24899]:0xe7b4df)
    at vlc_player_New (https://192.168.1.81:8443/test/update/experimental.wasm:wasm-function[24855]:0xe77376)

https://github.com/emscripten-core/emscripten/pull/15327