Specify desired protoc_gen_go_version on install

Signed-off-by: Sorin Dumitru <sorin@returnze.ro>

Author: sorindumitru

Makefile

@@ -142,7 +142,7 @@ $(protoc_gen_go_bin): | go-check
 	@echo "Installing protoc-gen-go $(protoc_gen_go_version)..."
 	@rm -rf $(protoc_gen_go_base_dir)
 	@mkdir -p $(protoc_gen_go_dir)
-	@$(go_path) go build -o $(protoc_gen_go_bin) google.golang.org/protobuf/cmd/protoc-gen-go
+	@GOBIN=$(protoc_gen_go_dir) $(go_path) go install google.golang.org/protobuf/cmd/protoc-gen-go@$(protoc_gen_go_version)
 
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 # protoc-gen-go-grpc