ARM: spitz: fix GPIO assignment for backlight

ARM: spitz: fix GPIO assignment for backlight

GPIOs controlling backlight on Spitz and Akita are coming from GPIO
expanders, not the pxa27xx-gpio block, correct it.

Additionally GPIO lookup tables operate with pin numbers rather than
legacy GPIO numbers, fix that as well. Use raw numbers instead of legacy
GPIO names to avoid confusion.

Fixes: ee0c8e494cc3 ("backlight: corgi: Convert to use GPIO descriptors")
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Link: https://lore.kernel.org/r/20240628180852.1738922-2-dmitry.torokhov@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>