USB: core: only clean up what we allocated

commit 32fd87b3bbf5f7a045546401dfe2894dbbf4d8c3 upstream.

When cleaning up the configurations, make sure we only free the number
of configurations and interfaces that we could have allocated.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>