greybus: arche-apb: Don't use gpio after failing to request it

If devm_gpio_request() returns an error, we shouldn't try to set the
direction of the same gpio.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>