Revert "ALSA: usb-audio: Notify xrun for low-latency mode"

This reverts commit 9bc69d38 which is
commit 4f9d6743 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I826fa2104760e1425393f48a1f16cd20257267d3
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>