qt: ensure libglib2 is built before qt if enabled for Qt's glib support

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/qt/qt.mk

@@ -48,6 +48,11 @@ else
 QT_CONFIGURE+= -no-qt3support
 endif
 
+# ensure glib is built first if enabled for Qt's glib support
+ifeq ($(BR2_PACKAGE_LIBGLIB2),y)
+QT_DEP_LIBS+=libglib2
+endif
+
 
 ### Pixel depths
 QT_PIXEL_DEPTHS := # empty