ALSA: Remove alsa timer from IRQ scheduling

As part of the setup for IRQ based scheduling, a period event was installed. Not only is a timer based polling unecessary for IRQ scheduling, depending on the state of the system, the timer could fire far enough from the IRQ, causing alsa wakeup events with no data in the ring buffer. Pipewire would identify these events as an "early wakeup", adding an extra quantum of time to the next_time estimate, skewing the clock and causing issues with apps that depend on precise timing.