AC3 3F1R downmix to stereo (simple downmixer)
AC3 3F1R downmix to stereo (simple downmixer)

Signed-off-by: Rémi Denis-Courmont <f0699137713be92736351a0674e79536595e4a60@remlab.net>

vlc-mirror/vlc-2.1,jomanmuk/vlc-2.2,vlc-mirror/vlc,shyamalschandra/vlc,krichter722/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc-2.1,jomanmuk/vlc-2.1,vlc-mirror/vlc,jomanmuk/vlc-2.2,krichter722/vlc,xkfz007/vlc,jomanmuk/vlc-2.1,jomanmuk/vlc-2.1,krichter722/vlc,xkfz007/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc,krichter722/vlc,shyamalschandra/vlc,vlc-mirror/vlc-2.1,jomanmuk/vlc-2.1,jomanmuk/vlc-2.2,shyamalschandra/vlc,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,vlc-mirror/vlc,vlc-mirror/vlc,shyamalschandra/vlc,vlc-mirror/vlc-2.1,vlc-mirror/vlc-2.1,shyamalschandra/vlc,krichter722/vlc,xkfz007/vlc,krichter722/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.2,vlc-mirror/vlc,vlc-mirror/vlc,xkfz007/vlc,xkfz007/vlc,jomanmuk/vlc-2.2,shyamalschandra/vlc,krichter722/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc-2.1,xkfz007/vlc,vlc-mirror/vlc-2.1,xkfz007/vlc