extensions: crude hack for mysterious cairo link failure

Why is /usr/lib64/libpixman-1.so not found automatically?

Change-Id: Ide3929b53d130aee44ff6b01dcf2f7491a61a09b

extensions/Executable_pluginapp.bin.mk

@@ -71,6 +71,10 @@ $(eval $(call gb_Executable_use_externals,pluginapp.bin,\
     gthread \
     gtk \
 ))
+# FIXME: on Fedora 19 link fails with unresolved symbols in cairo without this?
+$(eval $(call gb_Executable_add_libs,pluginapp.bin,\
+	-lpixman-1 \
+))
 
 # the orignal dmakefile said: don't ask, it's ugly
 ifeq ($(OS),SOLARIS)