Convert CONFIG_FSL_DCU_FB to Kconfig

Rename CONFIG_FSL_DCU_FB to CONFIG_VIDEO_FSL_DCU_FB
and convert it to Kconfig.

Signed-off-by: Sanchayan Maity <maitysanchayan@gmail.com>
Reviewed-by: Stefan Agner <stefan.agner@toradex.com>
Reviewed-by: Alison Wang <alison.wang@nxp.com>
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index db34904..7cd6d28 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -27,7 +27,7 @@
 obj-$(CONFIG_ATMEL_LCD) += atmel_lcdfb.o
 obj-$(CONFIG_CFB_CONSOLE) += cfb_console.o
 obj-$(CONFIG_FSL_DIU_FB) += fsl_diu_fb.o videomodes.o
-obj-$(CONFIG_FSL_DCU_FB) += fsl_dcu_fb.o videomodes.o
+obj-$(CONFIG_VIDEO_FSL_DCU_FB) += fsl_dcu_fb.o videomodes.o
 obj-$(CONFIG_L5F31188) += l5f31188.o
 obj-$(CONFIG_MPC8XX_LCD) += mpc8xx_lcd.o
 obj-$(CONFIG_PXA_LCD) += pxa_lcd.o