gpio: legacy interface cleanups for 7.3
These are the remaining patches for legacy gpio interface
cleanup, ensuring that files referencing them are sure to
have CONFIG_GPIOLIB_LEGACY set, and use linux/gpio/legacy.h
instead of the old linux/gpio.h header.
There are a few more patches already merged in other
branches for 7.3, including soc, led, net and media. Once
everything is in, we can apply the final patches to turn
off CONFIG_GPIOLIB_LEGACY by default and remove the obsolete
header file.
This branch is based on the immutable ib-mfd-legacy-gpio-7.3
branch from mfd.git to avoid a conflict in the rohm drivers.
8bdba6f6cf