Added buildx function for building multi-arch image

Makefile

@@ -103,6 +103,16 @@ IMAGE_BUILD_FLAGS ?= --build-arg USE_LOCAL=false
 OPERATOR_MAKE_ENV_FILE = local.mk
 -include $(OPERATOR_MAKE_ENV_FILE)
 
+# Buildx function for building multi-arch image
+define func_buildx
+	# copy existing Dockerfile and insert --platform=${BUILDPLATFORM} into Dockerfile.cross, and preserve the original Dockerfile
+	sed -e '1 s/\(^FROM\)/FROM --platform=\$$\{BUILDPLATFORM\}/; t' -e ' 1,// s//FROM --platform=\$$\{BUILDPLATFORM\}/' $1 > Dockerfile.cross
+	- docker buildx create --name project-v3-builder
+	docker buildx use project-v3-builder
+	- docker buildx build --push --platform=$2 --tag $3 -f Dockerfile.cross .
+	- docker buildx rm project-v3-builder
+	rm Dockerfile.cross
+endef
 
 .PHONY: default
 default: manifests lint unit-test build
@@ -185,13 +195,7 @@ build: generate fmt vet ## Build manager binary.
 PLATFORMS ?= linux/amd64,linux/s390x,linux/ppc64le
 .PHONY: docker-buildx
 docker-buildx: ## Build and push docker image for the manager for cross-platform support
-	# copy existing Dockerfile and insert --platform=${BUILDPLATFORM} into Dockerfile.cross, and preserve the original Dockerfile
-	sed -e '1 s/\(^FROM\)/FROM --platform=\$$\{BUILDPLATFORM\}/; t' -e ' 1,// s//FROM --platform=\$$\{BUILDPLATFORM\}/' ./Dockerfiles/Dockerfile > ./Dockerfiles/Dockerfile.cross
-	- docker buildx create --name project-v3-builder
-	docker buildx use project-v3-builder
-	- docker buildx build --push --platform=$(PLATFORMS) --tag ${IMG} -f ./Dockerfiles/Dockerfile.cross .
-	- docker buildx rm project-v3-builder
-	rm ./Dockerfiles/Dockerfile.cross
+	$(call func_buildx,./Dockerfiles/Dockerfile,$(PLATFORMS),$(IMG))
 
 .PHONY: run
 run: manifests generate fmt vet ## Run a controller from your host.
@@ -300,13 +304,7 @@ bundle-build: bundle
 
 .PHONY: bundle-docker-buildx
 bundle-docker-buildx: ## Build and push docker image for the manager for cross-platform support
-	# copy existing Dockerfile and insert --platform=${BUILDPLATFORM} into Dockerfile.cross, and preserve the original Dockerfile
-	sed -e '1 s/\(^FROM\)/FROM --platform=\$$\{BUILDPLATFORM\}/; t' -e ' 1,// s//FROM --platform=\$$\{BUILDPLATFORM\}/' ./Dockerfiles/bundle.Dockerfile > ./Dockerfiles/bundle.Dockerfile.cross
-	- docker buildx create --name project-v3-builder
-	docker buildx use project-v3-builder
-	- docker buildx build --push --platform=$(PLATFORMS) --tag ${BUNDLE_IMG} -f ./Dockerfiles/bundle.Dockerfile.cross .
-	- docker buildx rm project-v3-builder
-	rm ./Dockerfiles/bundle.Dockerfile.cross
+	$(call func_buildx,./Dockerfiles/bundle.Dockerfile,$(PLATFORMS),$(BUNDLE_IMG))
 
 .PHONY: bundle-push
 bundle-push: ## Push the bundle image.