Makefile changes to compile outside of docker

Change-Id: I21bda0e04024eddf0c6d513f6f0e208b7ec7710f
diff --git a/Makefile b/Makefile
index cd3402e..ba791e9 100644
--- a/Makefile
+++ b/Makefile
@@ -18,7 +18,13 @@
 
 .PHONY: dep test clean docker
 
-bbsim: protos/openolt.pb.go dep
+prereq:
+	go get -u google.golang.org/grpc
+	go get -v github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway
+	go get -v github.com/golang/protobuf/protoc-gen-go
+	go get -v github.com/google/gopacket
+
+bbsim: prereq protos/openolt.pb.go dep
 	go build -i -v -o $@
 
 dep: protos/openolt.pb.go