message: Remove unused part of Makefile
  Change-type: patch
diff: @@ -9,12 +9,6 @@ S3_BUCKET = artifacts.ci.balena-cloud.com
  # This directory will be completely deleted by the `clean` rule
  BUILD_DIRECTORY ?= dist
  -# See http://stackoverflow.com/a/20763842/1641422
  -BUILD_DIRECTORY_PARENT = $(dir $(BUILD_DIRECTORY))
  -ifeq ($(wildcard $(BUILD_DIRECTORY_PARENT).),)
  -$(error $(BUILD_DIRECTORY_PARENT) does not exist)
  -endif
  -
  BUILD_TEMPORARY_DIRECTORY = $(BUILD_DIRECTORY)/.tmp
  $(BUILD_DIRECTORY):
  @@ -91,7 +85,7 @@ TARGET_ARCH ?= $(HOST_ARCH)
  # ---------------------------------------------------------------------
  # Electron
  # ---------------------------------------------------------------------
  -electron-develop: | $(BUILD_TEMPORARY_DIRECTORY)
  +electron-develop:
  $(RESIN_SCRIPTS)/electron/install.sh \
  -b $(shell pwd) \
  -r $(TARGET_ARCH) \
  