video: Convert CONFIG_VIDEO_BCM2835 to Kconfig

This converts the following to Kconfig:
   CONFIG_VIDEO_BCM2835

This is the final ad-hoc CONFIG_VIDEO_... to convert.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Matthias Brugger <mbrugger@suse.com>
diff --git a/configs/rpi_4_defconfig b/configs/rpi_4_defconfig
index 461a765..eac55cc 100644
--- a/configs/rpi_4_defconfig
+++ b/configs/rpi_4_defconfig
@@ -59,6 +59,7 @@
 # CONFIG_VIDEO_BPP8 is not set
 # CONFIG_VIDEO_BPP16 is not set
 CONFIG_SYS_WHITE_ON_BLACK=y
+CONFIG_VIDEO_BCM2835=y
 CONFIG_CONSOLE_SCROLL_LINES=10
 CONFIG_PHYS_TO_BUS=y
 CONFIG_OF_LIBFDT_OVERLAY=y