Disable jemalloc when cross-building aarch64

[jtraglia]

This PR will disable jemalloc when cross-building the binary for aarch64-unknown-linux-gnu.

This reth binary is used here:

reth/Makefile

Lines 197 to 212 in 21bc1a8

	define build_docker_image
	$(MAKE) build-x86_64-unknown-linux-gnu
	mkdir -p $(BIN_DIR)/amd64
	cp $(BUILD_PATH)/x86_64-unknown-linux-gnu/$(PROFILE)/reth $(BIN_DIR)/amd64/reth
	$(MAKE) build-aarch64-unknown-linux-gnu
	mkdir -p $(BIN_DIR)/arm64
	cp $(BUILD_PATH)/aarch64-unknown-linux-gnu/$(PROFILE)/reth $(BIN_DIR)/arm64/reth
	docker buildx build --file ./Dockerfile.cross . \
	--platform linux/amd64,linux/arm64 \
	--tag $(DOCKER_IMAGE_NAME):$(1) \
	--tag $(DOCKER_IMAGE_NAME):$(2) \
	--provenance=false \
	--push
	endef

And correct binary is selected here:

reth/Dockerfile.cross

Line 12 in 21bc1a8

COPY ./dist/bin/$TARGETARCH/reth /usr/local/bin/reth

Fixes #6742.

[onbjerg]

looks good to me

[DaniPopes]

LGTM