interlacing: fix overlapping memory copy
interlacing: fix overlapping memory copy

(cherry picked from commit 2f1737e730e6e8844a93a32b236e36b16eb9bf33)

jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2