Add stratum-tofino driver

This patch also introduces a new driver property flag to indicate
whether a P4Runtime target supports default table entries or not.
Stratum targets built against the current version of p4lang/PI do not.

Change-Id: I1fbb57521516bee99057319ed1695cb05b68ee7c
diff --git a/drivers/barefoot/BUILD b/drivers/barefoot/BUILD
index f86f1e3..ee63540 100644
--- a/drivers/barefoot/BUILD
+++ b/drivers/barefoot/BUILD
@@ -15,9 +15,10 @@
 onos_app(
     app_name = "org.onosproject.drivers.barefoot",
     category = "Drivers",
-    description = "Adds support for Barefoot Networks devices",
+    description = "Adds support for switches based on Barefoot Networks ASICs",
     included_bundles = BUNDLES,
     required_apps = [
+        "org.onosproject.drivers.stratum",
         "org.onosproject.drivers.p4runtime",
     ],
     title = "Barefoot Drivers",