usb: gadget: ci13xxx: move endpoint (de-)initialization to probe/remove

Currently, endpoints are initialized in gadget start/stop methods, however
for the new style gadgets it is expected that bind() can be called before
controller's start(), and we need endpoints already initialized at that
point. So, move endpoint initialization to controller's probe before we
switch to the "new style" gadget framework.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>