Staging: greybus: gpio: Use gbphy_dev->dev instead of bundle->dev

Some of the print messages are using the incorrect device pointer, fix
them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>