extras/tools: set AUTOCONF variable so automake can find it
extras/tools: set AUTOCONF variable so automake can find it

use $(AUTOCONF) to make pkg-config, add dependancy on autoconf

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