[alsa-devel] ALSA: use irqsave() in URB completion + usb_fill_int_urb

This series is mostly about using _irqsave() primitives in the completion callback in order to get rid of local_irq_save() in __usb_hcd_giveback_urb(). While at it, I also tried to move drivers to use usb_fill_int_urb() otherwise it is hard find users of a certain API.

Sebastian