Update all Kconfig files and Makefiles to rely on the kernel overlay
feature. In particular, don't include any Kconfig files or Makefiles
from other overlays. -I directives in CFLAGS are not yet cleaned up.

Bug 1978395

Change-Id: I425d37d55f8ea61fb3a082a1504f994ff30cec03
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1561187


Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>