enc-amf: Update to version 1.4.3.9

1.4.3.9 is not an official version, it just patches a bug introduced by overusing a macro. I'm not sure if it fixes the crash in blog, but it should fix the crash in AMF initialization.

enc-amf @ 8648badf

-Subproject commit b0ccc1367afd73c3da99e314375bcbe2aa6675e5
+Subproject commit 8648badf4293b75106d018329b61a290fe8bb90b