Fail packages when artifacts are not found

By default the curl command returns exit status zero even
if the target URL returns a 404.

By using a -f (fail) option with curl makes the packaging
failing if any of the needed artifacts are missing.

Change-Id: I97370f1ea1a3c332cc1aee1459a1a77dced9044c
diff --git a/fpm/Makefile b/fpm/Makefile
index c5f0cd6..19deade 100644
--- a/fpm/Makefile
+++ b/fpm/Makefile
@@ -88,16 +88,16 @@
 	rm -Rf $(SCRIPTS_ROOT)
 
 $(WAR): $(basedir $(WAR))
-	curl -o $@  $(URL)
+	curl -f -o $@  $(URL)
 
 plugins:
 	for job in $(PLUGINS_JOBS); \
-          do curl -o $(BUILD_ROOT)/plugins/`basename $$job` $(PLUGINS_CI)/$$job; \
+          do curl -f -o $(BUILD_ROOT)/plugins/`basename $$job` $(PLUGINS_CI)/$$job; \
         done
 
 libs:
 	for job in $(LIBS_JOBS); \
-          do curl -o $(BUILD_ROOT)/lib/`basename $$job` $(PLUGINS_CI)/$$job; \
+          do curl -f -o $(BUILD_ROOT)/lib/`basename $$job` $(PLUGINS_CI)/$$job; \
         done
 
 $(SCRIPTS_ROOT)/%.sh: scripts/%.sh