sandbox: Move CONFIG_VIDEO_SANDBOX_SDL to Kconfig

Move this option to Kconfig. This is quite simple as only sandbox uses the
driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>

configs/sandbox_defconfig

 CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_PCI=y
 CONFIG_DEFAULT_DEVICE_TREE="sandbox"
+CONFIG_DM_PCI_COMPAT=y
 CONFIG_FIT=y
 CONFIG_FIT_VERBOSE=y
 CONFIG_FIT_SIGNATURE=y
@@ -51,7 +52,6 @@ CONFIG_SPI_FLASH_SST=y
 CONFIG_SPI_FLASH_WINBOND=y
 CONFIG_DM_ETH=y
 CONFIG_DM_PCI=y
-CONFIG_DM_PCI_COMPAT=y
 CONFIG_PCI_SANDBOX=y
 CONFIG_PINCTRL=y
 CONFIG_PINCONF=y
@@ -76,6 +76,7 @@ CONFIG_USB_EMUL=y
 CONFIG_USB_STORAGE=y
 CONFIG_USB_KEYBOARD=y
 CONFIG_SYS_USB_EVENT_POLL=y
+CONFIG_VIDEO_SANDBOX_SDL=y
 CONFIG_CMD_DHRYSTONE=y
 CONFIG_TPM=y
 CONFIG_LZ4=y

drivers/video/Kconfig

@@ -300,6 +300,15 @@ config DISPLAY_PORT
 	   to drive LCD panels. This framework provides support for enabling
 	   these displays where supported by the video hardware.
 
+config VIDEO_SANDBOX_SDL
+	bool "Enable sandbox video console using SDL"
+	depends on SANDBOX
+	help
+	  When using sandbox you can enable an emulated LCD display which
+	  appears as an SDL (Simple DirectMedia Layer) window. This is a
+	  console device and can display stdout output. Within U-Boot is is
+	  a normal bitmap display and can display images as well as text.
+
 config VIDEO_TEGRA124
 	bool "Enable video support on Tegra124"
 	help

include/configs/sandbox.h

@@ -159,7 +159,6 @@
 /* LCD and keyboard require SDL support */
 #ifdef CONFIG_SANDBOX_SDL
 #define CONFIG_LCD
-#define CONFIG_VIDEO_SANDBOX_SDL
 #define CONFIG_CMD_BMP
 #define CONFIG_BOARD_EARLY_INIT_F
 #define CONFIG_CONSOLE_MUX