Make sure usb class driver disconnect() functions are called properly.

disconnect() needs to be called exactly once per call to init_connection().
In case of bus resets, disconnect() was not called, which led to leaking
alloc_maximum() allocated buflib handles, which led to buflib running out
of memory to allocate.

Change-Id: I03025da578dc54e48b6de6bd3e3f40feae7220a6
1 file changed