Fixed deps and bundles for BMv2 drivers, P4Runtime and gRPC protocols

Change-Id: I96ad0e1e1021897544e41d02304a9f8240c1eb15
diff --git a/protocols/p4runtime/api/BUCK b/protocols/p4runtime/api/BUCK
index 21506be..b7d1869 100644
--- a/protocols/p4runtime/api/BUCK
+++ b/protocols/p4runtime/api/BUCK
@@ -1,6 +1,8 @@
+GRPC_VER = '1.3.0'
+
 COMPILE_DEPS = [
     '//lib:CORE_DEPS',
-    '//incubator/grpc-dependencies:grpc-core-repkg-1.3.0',
+    '//incubator/grpc-dependencies:grpc-core-repkg-' + GRPC_VER,
 ]
 
 TEST_DEPS = [