build: fix offline image build race condition

When generating the offline image list, the threaded crossbuild can
try to generate the image list from muliple jobs at once, resulting in
undefined behavior (usually an empty file) for the output file. To fix
this, we can generate this file in the `build.common` step which is not
run in parallel.

Signed-off-by: Blaine Gardner <blaine.gardner@redhat.com>

Makefile

@@ -107,6 +107,7 @@ build.version:
 build.common: build.version helm.build mod.check
 	@$(MAKE) go.init
 	@$(MAKE) go.validate
+	@$(MAKE) -C images/ceph list-image
 
 do.build.platform.%:
 	@$(MAKE) PLATFORM=$* go.build

images/ceph/Makefile

@@ -69,7 +69,6 @@ do.build:
 	@mkdir -p $(TEMP)/rook-external/test-data
 	@cp $(MANIFESTS_DIR)/create-external-cluster-resources.* $(TEMP)/rook-external/
 	@cp $(MANIFESTS_DIR)/test-data/ceph-status-out $(TEMP)/rook-external/test-data/
-	@$(MAKE) list-image
 
 ifeq ($(INCLUDE_CSV_TEMPLATES),true)
 	@$(MAKE) CSV_TEMPLATE_DIR=$(TEMP) generate-csv-templates