Fix errors in AMF library selection
Fix errors in AMF library selection

* a stupid mistake in 0b98d15 (misnamed member variable) effectively
  disabled the JS-only AMF library
* also fix a terrible copy-paste error masked by dumb error #1

KaiyonAlatar/eleven-server,Whizy/eleven-server,ElevenGiants/eleven-server,yelworc/eleven-server,ElevenGiants/eleven-server,KaiyonAlatar/eleven-server,KaiyonAlatar/eleven-server,ElevenGiants/eleven-server,yelworc/eleven-server,Whizy/eleven-server,Whizy/eleven-server