usb/uas: add usb_pipe_usage_descriptor

usb_pipe_usage_descriptor defines the struct which is used to describe
the type of the endpoint in UAS (status/command/data in+out). It will be
used by the UAS gadget, the host code is using a char array for the
access.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>