Merge branch 'dsa-add-mt7530-gpio-support'

DENG Qingfang says:

====================
dsa: add MT7530 GPIO support

MT7530's LED controller can be used as GPIO controller.
Add support for it.
====================

Link: https://lore.kernel.org/r/20210125044322.6280-1-dqfext@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>