Resume a particular channel.
void Mix_Resume(int channel);
|the channel to resume, or -1 to resume all paused channels.
It is legal to resume an unpaused or invalid channel; it causes no effect and reports no error.
If the paused channel has an expiration, its expiration countdown resumes now, as well.
Specifying a channel of -1 will resume all paused channels. Any music is unaffected.
This function is available since SDL_mixer 3.0.0.