gpiolib: Pass consumer device through to core in devm_fwnode_gpiod_get_index()
This devm API takes a consumer device as an argument to setup the devm
action, but throws it away when calling further into gpiolib. This leads
to odd debug messages like this:
(NULL device *): using DT '/gpio-keys/switch-pen-insert' for '(null)' GPIO lookup
Let's pass the consumer device down, by directly calling what
fwnode_gpiod_get_index() calls but pass the device used for devm. This
changes the message to look like this instead:
gpio-keys gpio-keys: using DT '/gpio-keys/switch-pen-insert' for '(null)' GPIO lookup
Note that callers of fwnode_gpiod_get_index() will still see the NULL
device pointer debug message, but there's not much we can do about that
because the API doesn't take a struct device.