Input: goodix - add support for controllers without flash

Some Goodix touchscreen controllers, such as for example the GT912,
don't have flash-storage for their firmware.

These models require the OS to load the firmware at runtime, as well as
some other special handling. Add support for this to the goodix driver.

This patch was developed and tested on a Glavey TM800A550L tablet.

Note the "goodix,main-clk" and "firmware-name" device-properties used
by the new code are *not* documented in the
Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
device-tree bindings for now.

Not documenting these is intentional. This is done because this code has
only been tested on x86/ACPI so far, where devicetree is not used.
Instead these properties are set through a software-fwnode attached to the
device by the drivers/platform/x86/touchscreen_dmi.c code. This means that
the use of this properties for now is purely a kernel-internal thing and
the name/working of the properties may still be changed for now.

Reviewed-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210920150643.155872-7-hdegoede@redhat.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>