This allows us to drop all of the custom config patching in
linux-raspberrypi.inc. It also allows the kernel config to be checked
during the build for any discrepancies between the selected config
options and the resulting .config file - this identified that
`CONFIG_DRM_VC4` depends on `CONFIG_SND` and `CONFIG_SND_SOC`.
Signed-off-by: Paul Barker <pbarker@konsulko.com>
Paul Barker