Convert CONFIG_VIDEO_OMAP3 to Kconfig

This converts the following to Kconfig:
   CONFIG_VIDEO_OMAP3

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/configs/mcx_defconfig b/configs/mcx_defconfig
index 3414640..8111238 100644
--- a/configs/mcx_defconfig
+++ b/configs/mcx_defconfig
@@ -50,6 +50,7 @@
 CONFIG_USB_HOST_ETHER=y
 CONFIG_USB_ETHER_ASIX=y
 CONFIG_USB_ETHER_MCS7830=y
+CONFIG_VIDEO_OMAP3=y
 CONFIG_VIDEO=y
 # CONFIG_VIDEO_SW_CURSOR is not set
 CONFIG_OF_LIBFDT=y