XCB/XVideo: add RV12, AV16 and AV32
XCB/XVideo: add RV12, AV16 and AV32

Those are not used (currently). This commit is only meant to avoid the
error messages for unknown formats.

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