drm/stm: lvds: add new STM32 LVDS Display Interface Transmitter driver

drm/stm: lvds: add new STM32 LVDS Display Interface Transmitter driver

The Low-Voltage Differential Signaling (LVDS) Display Interface
Transmitter handles the LVDS protocol: it maps the pixels received from
the upstream Pixel-DMA LCD-TFT Display Controller (LTDC) onto the LVDS
PHY.

It is composed of three sub blocks:
	* LVDS host: handles the LVDS protocol (FPD / OpenLDI) and maps
	  its input pixels onto the data lanes of the PHY
	* LVDS PHY: parallelize the data and drives the LVDS data lanes
	* LVDS wrapper: handles top-level settings

The LVDS controller driver supports the following high-level features:
	* FDP-Link-I and OpenLDI (v0.95) protocols
	* Single-Link or Dual-Link operation
	* Single-Display or Double-Display (with the same content
	  duplicated on both)
	* Flexible Bit-Mapping, including JEIDA and VESA
	* RGB888 or RGB666 output
	* Synchronous design, with one input pixel per clock cycle

Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
Acked-by: Yannick Fertre <yannick.fertre@foss.st.com>
Signed-off-by: Philippe Cornu <philippe.cornu@foss.st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240226-lvds-v6-2-15e3463fbe70@foss.st.com