meta-google: layer.conf: Add warrior compatibility

oe-core branched in preparation for the upcoming 2.7 Yocto release and
as of 13e45ff requires core layer compatibility to "warrior" instead of
"thud".  We'll retain compatibility for both until we do our own branch
or stop testing thud.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I73b53ab773f59954a9cbc2f779c2df6b6715be2e
1 file changed