USB: don't read past config->interface[] if usb_control_msg() fails in usb_reset_conf...

While looping over the interfaces, if usb_hcd_alloc_bandwidth() fails it calls
hcd->driver->reset_bandwidth(), so there was no need to reinstate the interface
again.

If no break occurred, the index equals config->desc.bNumInterfaces. A
subsequent usb_control_msg() failure resulted in a read from
config->interface[config->desc.bNumInterfaces] at label reset_old_alts.

In either case the last interface should be skipped.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>