[PATCH v1 1/3] sound: usb: Add vendor's hooking interface

[Christoph Hellwig]

Independ of the actual usefulness of thi: vendor is a reallly bogus
naming choice for device specific hooks.  No one cares what vendor
produces a given device, it is all about the interface of it.  One
vendor might have different interfaces over time, from different
divisons or thrugh acquisitions, and multiple vendors can agree to
a single interface through open standards or IP licensing.