staging: gasket: gasket_handle_ioctl fix ioctl exit trace param

Pass the return value from the device ioctl permissions callback to the
tracepoint when the callback returns an error.

Reported-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>