edison: move audio/usb to audio/generic/usb Cherry-picked again by [email protected] due to change being skipped by auto-merger. BUG=none Tracked-On: https://jira01.devtools.intel.com/browse/BP-175 Signed-off-by: teng jin chung <[email protected]> Signed-off-by: Bruce Beare <[email protected]> Change-Id: Ie5ec9957acdd6231961c28e5492b20cf584fb54e