tools: require autoconf version 2.69 or higher
tools: require autoconf version 2.69 or higher

Signed-off-by: Rafaël Carré <29a40ef51885229607cd1e19e467be5d13190cad@videolan.org>
(cherry picked from commit d2ff1914069d054c2a0a3c13825faccb81c64546)
Signed-off-by: Felix Paul Kühne <af44a38b4065def9b90f0b66e4658837dd45b77d@videolan.org>

jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2