Bump DVBsub priority above avcodec
Bump DVBsub priority above avcodec

Since now avcodec module accepts dvbsub, it is always taken, even if it
fails to decode...

Close #10655

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