added necessary library for pdf export on Android Viewer

Change-Id: I01413493100fd110175ec85790899a130954c78e
Signed-off-by: Mert Tumer <merttumer@outlook.com>
Reviewed-on: https://gerrit.libreoffice.org/58688
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

solenv/bin/native-code.py

@@ -60,6 +60,7 @@ core_factory_list = [
     ("libmcnttype.a", "mcnttype_component_getFactory"),
     ("libvcllo.a", "vcl_component_getFactory"),
     ("libspelllo.a", "spell_component_getFactory"),
+    ("libpdffilterlo.a", "pdffilter_component_getFactory"),
     ("libsvgiolo.a", "svgio_component_getFactory")
     ]