We need to update the LICENSE file to match OpenJDK and add the missing ADDITIONAL_LICENSE_INFO and ASSEMBLY_EXCEPTION files.
Note that the OpenJDK LICENSE file was modified by JDK-8154469 to update the FSF address, so we just need to apply that patch (or copy the file from OpenJDK). The other two files have never been in OpenJFX, but need to be. Note that the ADDITIONAL_LICENSE_INFO file was recently added by JDK-8193208; the ASSEMBLY_EXCEPTION file has been there since the early days of OpenJDK.