[Unifex] Implicit cast warning in functions enif_get_int64() and enif_get_long()

[maksstach]

When compiling membrane_h264_ffmpeg_plugin the unifex generated code raises a warning:

~/Projects/membrane_h264_ffmpeg_plugin master ❯ mix compile                                                                                                  13:30:46
Bundlex: Building natives: parser, decoder, encoder
/Users/maksstachowiak/Projects/membrane_h264_ffmpeg_plugin/c_src/membrane_h264_ffmpeg_plugin/_generated/nif/decoder.c:183:37: warning: incompatible pointer types passing 'int64_t *' (aka 'long long *') to parameter of type 'long *' [-Wincompatible-pointer-types]
  if (!enif_get_int64(env, argv[1], &dts)) {
                                    ^~~~
/Users/maksstachowiak/.asdf/installs/erlang/24.0.5/usr/include/erl_nif_api_funcs.h:104:79: note: passing argument to parameter 'ip' here
ERL_NIF_API_FUNC_DECL(int,enif_get_long,(ErlNifEnv*, ERL_NIF_TERM term, long* ip));
                                                                              ^
1 warning generated.
/Users/maksstachowiak/Projects/membrane_h264_ffmpeg_plugin/c_src/membrane_h264_ffmpeg_plugin/_generated/nif/encoder.c:258:37: warning: incompatible pointer types passing 'int64_t *' (aka 'long long *') to parameter of type 'long *' [-Wincompatible-pointer-types]
  if (!enif_get_int64(env, argv[1], &pts)) {
                                    ^~~~
/Users/maksstachowiak/.asdf/installs/erlang/24.0.5/usr/include/erl_nif_api_funcs.h:104:79: note: passing argument to parameter 'ip' here
ERL_NIF_API_FUNC_DECL(int,enif_get_long,(ErlNifEnv*, ERL_NIF_TERM term, long* ip));
                                                                              ^
1 warning generated.

The definition of long is platform dependent.
fix: explicitly cast the argument to functions enif_get_int64() and enif_get_long() to type ErlNifUInt64