Support for startup node multi-arch variant selection through startup.conf.
This is to facilitate unit, functional testing and benchmarking of non-default
multi-arch variant node code path. Also added parameters to make test, to
specific using multi-arch variants in unit testing.
Type: improvement
Signed-off-by: Ray Kinsella <mdr@ashroe.eu>
Change-Id: I94fd332bb629683b7a7dd770ee9f615a9a424060