snd_config_imul always produces a zero result.

[GitHub issues - opened <github@alsa-project.org>]

alsa-project/alsa-lib issue #456 was opened from shanekirk:

The config function snd_config_imul always produces a zero result. This is because it delegates to snd_func_iops() to perform the iterative multiplication, which always initializes its result value to zero. Then it iteratively multiplies-assigns result against each integer in the params array, which _always_ produces zero.

This breaks any configuration that leans on "@func imul".

This can be demonstrated using this snippet of configuration...

```
test_fn
{
    @func imul
    integers [2 4 6]
}

```
...or this source code...
```
int main(int argc, char **argv)
{
    snd_config_t *pConfig = NULL;
    snd_config_top(&pConfig);

    /**
     * Setting up...
     * test_fn
     * {
     *     @func imul
     *     integers [2 4 6]
     * }
     */
    snd_config_t *pFnCS = NULL;
    snd_config_make_compound(&pFnCS, "test_fn", 0);
    snd_config_add(pConfig, pFnCS);

    snd_config_t *pFn = NULL;
    snd_config_imake_string(&pFn, "@func", "imul");
    snd_config_add(pFnCS, pFn);

    snd_config_t *pFnParams = NULL;
    snd_config_make_compound(&pFnParams, "integers", 0);
    snd_config_add(pFnCS, pFnParams);

    snd_config_t *pFnInt = NULL;
    snd_config_imake_integer(&pFnInt, "0", 2);
    snd_config_add(pFnParams, pFnInt);
    snd_config_imake_integer(&pFnInt, "1", 4);
    snd_config_add(pFnParams, pFnInt);
    snd_config_imake_integer(&pFnInt, "2", 6);
    snd_config_add(pFnParams, pFnInt);

    /**
     * Evaluating...
     */
    snd_config_evaluate(pFnCS, pConfig, NULL, NULL);
    assert(snd_config_get_type(pFnCS) == SND_CONFIG_TYPE_INTEGER);
    long result = 0;
    snd_config_get_integer(pFnCS, &result);
    assert(result == 48); // ** FAILS because result is always zero! **

    snd_config_delete(pConfig);
    return 0;
}
```

Note: If you replace "imul" above with "iadd" in either example, you'll get the result from iadd that you'd expect.

Issue URL     : https://github.com/alsa-project/alsa-lib/issues/456
Repository URL: https://github.com/alsa-project/alsa-lib