video: move tegra dc driver into own folder

Move tegra dc driver to tegra20 directory and also mention
T30 in description of the driver's config option.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
[agust: add commit description]
Signed-off-by: Anatolij Gustschin <agust@denx.de>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 60f4a4b..334d64c 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -668,15 +668,6 @@
 
 source "drivers/video/tidss/Kconfig"
 
-config VIDEO_TEGRA20
-	bool "Enable LCD support on Tegra20"
-	depends on OF_CONTROL
-	help
-	   Tegra20 supports video output to an attached LCD panel as well as
-	   other options such as HDMI. Only the LCD is supported in U-Boot.
-	   This option enables this support which can be used on devices which
-	   have an LCD display connected.
-
 config VIDEO_TEGRA124
 	bool "Enable video support on Tegra124"
 	help
@@ -687,6 +678,8 @@
 
 source "drivers/video/bridge/Kconfig"
 
+source "drivers/video/tegra20/Kconfig"
+
 source "drivers/video/imx/Kconfig"
 
 config VIDEO_MXS