aseqsend getopt_long variable should be int instead of char

[GitHub issues - opened <github@xxxxxxxxxxxxxxxx>]

alsa-project/alsa-utils issue #274 was opened from sadguitarius:

Hi, just wanted to point out that aseqsend is failing because the value returned by getopt_long can never be -1 since it's a char.

Issue URL     : https://github.com/alsa-project/alsa-utils/issues/274
Repository URL: https://github.com/alsa-project/alsa-utils