MFH: r449689

multimedia/ffmpeg: update to 3.3.4

Changes: https://git.ffmpeg.org/gitweb/ffmpeg.git/blob/n3.3.4:/Changelog
ABI: https://abi-laboratory.pro/tracker/timeline/ffmpeg/
Security: CVE-2017-14054 CVE-2017-14055 CVE-2017-14056 CVE-2017-14057
Security: CVE-2017-14058 CVE-2017-14059 CVE-2017-14169 CVE-2017-14170
Security: CVE-2017-14171 CVE-2017-14222 CVE-2017-14223 CVE-2017-14225

Approved by: ports-secteam (with hat)