gpiolib: generalize devprop_gpiochip_set_names() for device properties

devprop_gpiochip_set_names() is overly complicated with taking the
fwnode argument (which requires using dev_fwnode() & of_fwnode_handle()
in ACPI and OF GPIO code respectively). Let's just switch to using the
generic device properties.

This allows us to pull the code setting line names directly into
gpiochip_add_data_with_key() instead of handling it separately for
ACPI and OF.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>