Platform: i.MX8MP EVK , L6.1.22-2.0.0
LT9211 is a chip that can realize the conversion of MIPI DSI signals to LVDS signals. This patch is based on this mainline driver:https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/drivers/gpu/drm/bridge/lontium-lt9211.c
Move lt9211_host_attach function to lt9211_attach to skip bridge attach error.
