Fix dockerized proto build

Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>

Author: marquiz

Makefile

@@ -193,7 +193,7 @@ check-protoc:
 	fi
 
 install-protoc install-protobuf:
-	$(Q)PROTOBUF_VERSION=$(PROTOBUF_VERSION) ./scripts/install-protobuf
+	$(Q)PROTOBUF_VERSION=$(PROTOBUF_VERSION) INSTALL_DIR=$(PROTOC_PATH) ./scripts/install-protobuf
 
 clean-protoc:
 	$(Q)rm -rf $(PROTOC_PATH)

hack/Dockerfile.buildproto

@@ -23,12 +23,9 @@ WORKDIR /go/src
 RUN apt-get update && apt-get install -y unzip
 
 RUN --mount=type=cache,target=/go/pkg/mod/ \
-    --mount=src=.,target=. \
-    make install-protoc-dependencies install-ttrpc-plugin install-wasm-plugin install-protoc
-
-RUN --mount=type=cache,target=/go/pkg/mod/ \
+    --mount=type=cache,target=/go/tools/,sharing=private \
     --mount=src=.,target=.,rw=true \
-    make build-proto && \
+    make build-proto PROTOC_PATH=/go/tools/protoc && \
     tar czf /artifacts.tgz ${ARTIFACTS}
 
 FROM scratch AS final

scripts/install-protobuf

@@ -24,7 +24,7 @@ PROTOBUF_VERSION=${PROTOBUF_VERSION-3.20.1}
 GOARCH=$(go env GOARCH)
 GOOS=$(go env GOOS)
 PROTOBUF_DIR=$(mktemp -d)
-INSTALL_DIR="$PWD/build/tools/protoc"
+INSTALL_DIR=${INSTALL_DIR-"$PWD/build/tools/protoc"}
 
 mkdir -p "$INSTALL_DIR"