build: add class specific GLUON_SITE_PACKAGES

This allows to define a list of packages, which are only installed
for a specific device-class.

Makefile

@@ -133,8 +133,8 @@ ifneq ($(filter __ERROR__,$(GLUON_FEATURES_standard) $(GLUON_FEATURES_tiny)),)
 endif
 
 $(eval $(call merge_lists,GLUON_DEFAULT_PACKAGES,$(GLUON_DEFAULT_PACKAGES) $(GLUON_SITE_PACKAGES)))
-$(eval $(call merge_lists,GLUON_CLASS_PACKAGES_standard,$(GLUON_FEATURE_PACKAGES_standard)))
-$(eval $(call merge_lists,GLUON_CLASS_PACKAGES_tiny,$(GLUON_FEATURE_PACKAGES_tiny)))
+$(eval $(call merge_lists,GLUON_CLASS_PACKAGES_standard,$(GLUON_FEATURE_PACKAGES_standard) $(GLUON_SITE_PACKAGES_standard)))
+$(eval $(call merge_lists,GLUON_CLASS_PACKAGES_tiny,$(GLUON_FEATURE_PACKAGES_tiny) $(GLUON_SITE_PACKAGES_tiny)))
 
 
 LUA := openwrt/staging_dir/hostpkg/bin/lua

docs/user/site.rst

@@ -545,6 +545,14 @@ GLUON_SITE_PACKAGES
     default package set. It is also possible to remove packages from the
     default set by prepending a minus sign to the package name.
 
+GLUON_SITE_PACKAGES_standard
+    Defines a list of additional packages to include or exclude for devices of
+    the standard device-class.
+
+GLUON_SITE_PACKAGES_tiny
+    Defines a list of additional packages to include or exclude for devices of
+    the tiny device-class.
+
 GLUON_RELEASE
     The current release version Gluon should use.