check am.mvn exists

lyblsgo

2023-04-25 6ef5ccc784d9f7fcd4072dd83c6ceaf1c324b92c

 funasr/runtime/onnxruntime/src/paraformer.cpp

@@ -147,6 +147,10 @@
void Paraformer::LoadCmvn(const char *filename)
{
    ifstream cmvn_stream(filename);
    if (!cmvn_stream.is_open()) {
        LOG(ERROR) << "Failed to open file: " << filename;
        exit(0);
    }
    string line;

    while (getline(cmvn_stream, line)) {