Add meta-agl-kuksa-val

Add meta-agl-kuksa-val

Add new meta-agl-kuksa-val layer, and populate it with the base
KUKSA.val databroker and VSS schema recipes from meta-agl, as well
as the recipes for the Python modules they depend on.

Additional changes:
- Installation of AGL-specific configuration has been removed from
  the kuksa-can-provider recipe.  It now packages the upstream
  example/test configuration in a new kuksa-can-provider-conf-example
  package that can be replaced via the RPROVIDES scheme.  Some minor
  tweaks for paths are made to the upstream .ini file to match
  FHS expectations.

Bug-AGL: SPEC-5136

Change-Id: I3128a223f4fcf16e496cb27e26afcaee0a28979a
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/30040
Tested-by: Jenkins Job builder account
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>