boards: cxd56xx: Add VIDEO configuration to mpy defconfig

New CISIF which supports rearchitected video driver needs VIDEO configuration.
Add VIDEO configuration because mpy defconfig includes CISIF.

boards/arm/cxd56xx/spresense/configs/mpy/defconfig

@@ -43,6 +43,7 @@ CONFIG_CXD56_UART2=y
 CONFIG_CXD56_USBDEV=y
 CONFIG_DEBUG_FULLOPT=y
 CONFIG_DEBUG_SYMBOLS=y
+CONFIG_DRIVERS_VIDEO=y
 CONFIG_FAT_LCNAMES=y
 CONFIG_FAT_LFN=y
 CONFIG_FAT_MAXFNAME=255
@@ -93,3 +94,4 @@ CONFIG_USBMSC=y
 CONFIG_USBMSC_EPBULKIN=1
 CONFIG_USBMSC_REMOVABLE=y
 CONFIG_USER_ENTRYPOINT="spresense_main"
+CONFIG_VIDEO_STREAM=y