package/gupnp-dlna: add introspection support

- introspection support is needed to build latest rygel version
- build vala bindings to avoid a build failure as already done in other
  packages such as gssdp in commit
  d513e55930eda15a5fb15e00c1da774e6c18f66c

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/gupnp-dlna/gupnp-dlna.mk

@@ -15,9 +15,14 @@ GUPNP_DLNA_LICENSE_FILES = COPYING
 GUPNP_DLNA_INSTALL_STAGING = YES
 GUPNP_DLNA_DEPENDENCIES = host-pkgconf libglib2 libxml2
 
-GUPNP_DLNA_CONF_OPTS = \
-	--disable-introspection \
-	--disable-legacy-gstreamer-metadata-backend
+GUPNP_DLNA_CONF_OPTS = --disable-legacy-gstreamer-metadata-backend
+
+ifeq ($(BR2_PACKAGE_GOBJECT_INTROSPECTION),y)
+GUPNP_DLNA_CONF_OPTS += --enable-introspection
+GUPNP_DLNA_DEPENDENCIES += host-vala gobject-introspection
+else
+GUPNP_DLNA_CONF_OPTS += --disable-introspection
+endif
 
 ifeq ($(BR2_PACKAGE_GST1_PLUGINS_BASE),y)
 GUPNP_DLNA_CONF_OPTS += --enable-gstreamer-metadata-backend