video: restore CONFIG_VIDCONSOLE_AS_LCD as boolean

This patch restores CONFIG_VIDCONSOLE_AS_LCD as boolean
and introduce a separate sting as CONFIG_VIDCONSOLE_AS_NAME
to search this string in stdout used as videoconsole.

This patch avoid issue with board defconfig or code expecting
CONFIG_VIDCONSOLE_AS_LCD as boolean.

Fixes: 22b897a12323 ("video: extend stdout video console work-around for 'vga'")
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 52f5bc6..0cf13ad 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -177,8 +177,18 @@
 source "drivers/video/fonts/Kconfig"
 
 config VIDCONSOLE_AS_LCD
-	string "Use 'vidconsole' when string defined here is seen in stdout"
+	bool "Use 'vidconsole' when CONFIG_VIDCONSOLE_AS_NAME string is seen in stdout"
 	depends on DM_VIDEO
+	help
+	  This is a work-around for boards which have 'lcd' or 'vga' in their
+	  stdout environment variable, but have moved to use driver model for
+	  video. In this case the console will no-longer work. While it is
+	  possible to update the environment, the breakage may be confusing for
+	  users. This option will be removed around the end of 2020.
+
+config VIDCONSOLE_AS_NAME
+	string "Use 'vidconsole' when string defined here is seen in stdout"
+	depends on VIDCONSOLE_AS_LCD
 	default "lcd" if LCD || TEGRA_COMMON
 	default "vga" if !LCD
 	help