Function check_need_full_bench

dnn/test/rocm/chanwise_convolution.cpp:20–25

#if MEGDNN_WITH_BENCHMARK
bool check_need_full_bench() {
    if (getenv("MEGDNN_CHANWISE_CONV_FULLBENCH"))
        return true;
    printf("set MEGDNN_CHANWISE_CONV_FULLBENCH to run full benchmark\n");
    return false;
}
#endif

Convolution::Param gconv_param(Convolution::Param p) {