device: Move MIPI panel library from mainboard/google/kukui into common

All boards that are trying to use MIPI panels eventually run into the
problem that they need to store physical parameters and a list of DCS
initialization commands for each panel, and these commands can be very
different (e.g. a large amount of very short commands, a few very large
commands, etc.). Finding a data format to fit all these different cases
efficiently into the same structures keeps being a challenge, and the
Kukui mainboard already once put a lot of effort into designing a
clean, flexible and efficient solution for this. This patch moves that
framework into a common src/device/mipi/ library where it can be used by
other boards as well. (Also, this will hopefully allow us to save some
duplicated work when using the same panel on different boards at some
point.)

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I877f2b0c7ab984412b288e2ed27f37cd93c70863
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56965
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>

src/device/Kconfig

@@ -1,5 +1,7 @@
 ## SPDX-License-Identifier: GPL-2.0-only
 
+source "src/device/mipi/Kconfig"
+
 menu "Devices"
 
 config HAVE_VGA_TEXT_FRAMEBUFFER