Merge pull request #2337 from freifunk-gluon/makefile-fixes

Makefile

@@ -19,8 +19,9 @@ escape = '$(subst ','\'',$(1))'
 GLUON_SITEDIR ?= site
 $(eval $(call mkabspath,GLUON_SITEDIR))
 
-$(GLUON_SITEDIR)/site.mk:
-	$(error No site configuration was found. Please check out a site configuration to $(GLUON_SITEDIR))
+ifeq ($(realpath $(GLUON_SITEDIR)/site.mk),)
+$(error No site configuration was found. Please check out a site configuration to $(GLUON_SITEDIR))
+endif
 
 include $(GLUON_SITEDIR)/site.mk
 
@@ -70,7 +71,7 @@ GLUON_VARS = \
 	GLUON_VERSION GLUON_SITE_VERSION \
 	GLUON_RELEASE GLUON_REGION GLUON_MULTIDOMAIN GLUON_AUTOREMOVE GLUON_DEBUG GLUON_MINIFY GLUON_DEPRECATED \
 	GLUON_DEVICES GLUON_TARGETSDIR GLUON_PATCHESDIR GLUON_TMPDIR GLUON_IMAGEDIR GLUON_PACKAGEDIR GLUON_DEBUGDIR \
-	GLUON_SITEDIR GLUON_RELEASE GLUON_AUTOUPDATER_BRANCH GLUON_AUTOUPDATER_ENABLED GLUON_LANGS GLUON_BASE_FEEDS \
+	GLUON_SITEDIR GLUON_AUTOUPDATER_BRANCH GLUON_AUTOUPDATER_ENABLED GLUON_LANGS GLUON_BASE_FEEDS \
 	GLUON_TARGET BOARD SUBTARGET
 
 unexport $(GLUON_VARS)