We're planning to remove the gpiochip_add() function to swith
to gpiochip_add_data() with NULL for data argument.

Cc: linux-mips@linux-mips.org
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>