vmem: unlock picture in prepare, get rid of lock/unlock
vmem: unlock picture in prepare, get rid of lock/unlock

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